Terminal servers are a funny animal. I am not so sure about progression as we run ES here with users running full desktops and just published app mode.
1) /install mode - (good to see you found), you can also perform via control panel -> programs -> "install application on remote desktop" for a GUI version. And of course make sure
no one is connected to the server while you install.
2) I have had to install the app via the console at not RDP'd into the terminal server. I know for MS Office and sometimes printers this is true for some versions.
3) Try installing as the local server administrator instead of a user with administrative rights.
4) The directory you installed to may have logging writing there. As such those specific directories may need to be opened for read/write access to the "users" group on the server. I would not just open program files directory, but the least number of directories.
4a) There is a tool "Process Monitor" free from microsoft [
technet.microsoft.com/en-us/sysinternals/processmonitor.aspx] that can help find these types of permission issues.
5) I see you are mapping a drive, perhaps use a UNC path instead might be better.
Good luck!