Gotchas installing XenApp 6 Beta for Windows 2008 R2

Had a fun day or two installing the new Beta for XenApp 6, the Windows 2008 R2 only version.  This is an version I had been waiting for for a while since I've found XenApp 5's performance on Windows 2008 to be rather underwhelming unless its installed on a beast of a server.

Anyway, XenApp 6 (okay, so Citrix aren't calling it that at yet officially, but its plastered all over the thing under the hood and in the documentation - its XenApp 6, honest) is still a Tech Preview and is a little fiddly.  I fell into the following elephant traps while installing it.

• License server.  I didn't have a Windows 2008 R2 License Server (only R1), which Terminal Services (sorry, RDS, Microsoft have been at the renaming juice too) wasn't impressed by.  Turns out Windows Server 2008 R2 makes quite a good Terminal Services License server since it can serve licenses for all the server versions from 2000 up to 2008 R2, so we now have a new License server for all our TS servers!  The Tech Preview DVD image comes with the latest full version of License Server, 11.6.1, which finally has a user interface written this century.  Sometimes Citrix change things for the sake of change, but this is a very welcome refresh.
• XenApp 6 Tech Preview licenses.  In my simple way I thought I could just use actual Citrix licenses for the Tech Preview - nope, it needs fake ones!  Could not find the things anywhere (they're not part of the download, annoyingly) so posted the question to the Citrix Forums site and got a response within about 2 minutes!  That's service.  Anyway, they're here:
  http://www.citrix.com/English/mycitrix/resources.asp?contentID=1860995#top
• Mixed Farms.  Yes, I tried to join my XenApp 6 servers to my XenApp 5 farm.  No joy.  No mixed farms.
• Program Neighbourhood.  I was using this to test my apps but could not connect to the new farm - old habits die hard!  Anyway, unless I am being a muppet, XenApp 6 does not support Program Neighbourhood - makes sense since it has been officially dropped for all products by Citrix and is not part of the client download since v11.1 last year.  Connected with the XenApp Agent and Web Interface fine.
• License Server (again).  Needs specifying for all the servers - and its not where it used to be.  There is now a new "Policies" node in the XenApp Management tool which is basically a version of the Group Policies Management Console and this needed configuring.  Entered my server name in the Unfiltered policy and finally was able to launch applications!
• Streamed Apps.  Oh yes, and I wanted to use my existing streamed profiles.  No joy, had to install ANOTHER 2008 R2 server (now up to 4 for this test environment - XenApp server, License Server, Profiler and Web Interface - oh, and a database elsewhere!) and the exciting beta of the new version of the Streaming Profiler.   Okay, its not exciting, though I like the fact it supports services. 

Anyway, its all up and running now and looking very nice.  Its already performing better than our XenApp 5 Farm on the same standard hardware - specifically it does not have the same problems with ever expanding logon times above about 75 users per server.  Its lovely.  I want the full version now!