This post describes the method’s involved in creating Application Layers and Elastic Layers to be used in a Unidesk environment running on Hyper-V with XenDesktop and Citrix PVS. This post assumes you have the Unidesk Enterprise Layer Manager appliance installed, configured and an OS Layer in place.
To install and configure the ELM in Hyper-V – http://www.jgspiers.com/installing-configuring-unidesk-4/
To install and configure an OS Layer, including Platform Layer and Image Template – http://www.jgspiers.com/create-update-os-layer-unidesk-4/
As mentioned, this guide runs Unidesk on Hyper-V. To see how to layer applications in VMware, see Carl Stalhood’s guide Unidesk App Layers, Image Templates, and Reporting.
♣ Creating an Application Layer
♣ Publishing Elastic Layers
Creating an Application Layer
This guide assumes that you already have an OS Layer in place. If not, read the above posts. An Application Layer is tied to one OS Layer. That means, you can’t assign an Application Layer to both a Windows 10 OS Layer and Windows 7 OS Layer. The Application Layer remains tied to the OS Layer that was used during the packaging of that layer. This post shows how to package and deploy Adobe Reader DC as an Application Layer, and then later on in the post assigning Google Chrome as an Elastic Layer.
Log on to the UMC and navigate to Layers -> App Layers -> Create App Layer.
Specify a name, version, descriptions and layer size in GB. The layer will be thin provisioned. Make the layer size large enough to host the application. 
Choose the OS Layer you want to use to create this layer. This layer will then later become deployable only with this selected OS Layer. 
If your layer needs prerequisite layers, you would specify them here. Those layers would then be available to you on the Packaging Machine.
Since we are using Hyper-V, choose the ELM Share connector. Virtual boot and package disks will be available on this share, and then we will attach those disks to a Packaging Machine to perform the application installation. 
If you are installing the application on a different hypervisor than what was used to create the OS Layer, you would include a Platform Layer for packaging which includes the necessary hypervisor tools to support your application install. I do not need this, so will continue on.
Keep the default values and click the down arrow. 
Upload an image icon that represents the application you are installing. To do so, click the Browse button. 
Click Create Layer. 
Expand the Application Layer creation task. You will be notified that a boot and packaging disk is available within the ELM Share. 
Browse to the ELM Share and you will see the required disks in the Packaging Disks folder. Attach these disks to a virtual machine which will be used as your Packaging Machine. Unlike the OS Layer and Platform Layer, it is not required that you add a Legacy NIC to the Packaging VM. You can stick to using a Synthetic NIC. Attach the disks and boot the VM.
Install the application, making any necessary modifications to block automatic updates or other user prompts. The Internet is a good place to start for looking up such modifications.
Once the application install is complete run Shutdown For Finalize. If an NGEN operation or reboot is required you will be notified to complete such tasks before the machine can be finalized.
Move the boot and package disks to the Finalize Disks folder within the ELM Share. 
Navigate back to the UMC and click on the Adobe Reader layer -> Finalize. 
Here you have the option to specify a Script Path. Scripts are useful for applications that need post-install configuration tasks such as licensing the product. Click the down arrow.
Click Finalize. 
A new task appears in the UMC.
Now the layer has been created and is ready to use. 
To publish an application out you need to add it to an Image Template. You can also elastically assign it to users or groups which I will show later. Edit your existing Image Template which contains the correct OS Layer, click on the Application Assignment tab and then check the Application Layer. 
Click Save Template Changes. 
Now click Publish Layered Image to publish the image to PVS, for example. 
Once the image has been published, attach it to a Target Device and boot. Test that the application shows and performs as expected. The application appears in Add/Remove Programs.
It also appears in Program Files, looking just like a local install.
You can also add Application Layers to Image Templates by selecting an Application Layer and then clicking on Add Assignments. 
Now select an available Image Template to attach this Application Layer to. Likewise you can use the Update Assignments and Remove Assignments buttons to perform update and remove tasks.
You are done. You have now successfully created and published an Application Layer.
Assigning layers elastically using Elastic Layering
As the name suggests, you can dynamically assign layers to groups and individual users right as they log on. You should already have an OS Layer published which is configured for Elastic Layering. Not all applications are suitable for Elastic Layering. Some applications require loading low-level drivers which makes them a bad candidate for Elastic Layering. You can to the best of Unidesk’s knowledge analyze a layer to see if it would work with elastically. Keep in mind that you do need to perform your own testing of the application, do not take Unidesk’s word for it. Click on an Application Layer, in my example Google Chrome and click Analyze Layer. 
Click the down arrow. 
Click Analyze Layer Versions. 
A new task completes once the analysis is done. 
Select the application again and click Add Assignments. 
Click on the Elastic Assignment tab. You can see that a message appears saying This layer should work when deployed elastically. Whilst you are here, this is the page you can use to assign a layer elastically to groups or individual users. For this example, I am assigning Google Chrome as an Elastic Layer to the EL – Google Chrome group. Unidesk recommend creating a group in Active Directory for each Elastic Layer.
Click Assign Layer. 
At this stage the layer will be copied to the ELM Share. 
Browse to the ELM Share and you will find two new .json files. 
The ElasticLayerAssignments.json file shows the group assignment name EL – Google Chrome and the layer ID 3866628.
The Layers.json file shows the same layer ID 3866628 and the name of the Application Layer Google Chrome. 
Inside the Unidesk\Layers\ folder is a newly created App folder containing the Google Chrome layer disk. Notice it also has the layer ID mentioned in the file name. 
Logging on to the OS Layer as a user who is a member of the EL – Google Chrome group prompts the Unidesk Elastic Layer service to layer in Google Chrome. 
Event Viewer also shows an event showing the user who logged on and which layer was attached.
When I log on as a user not in the group, Event Viewer reports that no layer was attached. 
Google Chrome does not show in Add/Remove programs, even though another user is using that layer on the same server. 
Google Chrome folders do exist in C:\ however this is a known bug. All folders are actually empty so you won’t find any files in them. 