I am trying to install Flash Professional CC to a location other than my C: drive

Have you tried creating a "user" file in E: (E:\Users\name) and also choosing it as the default Folder location under "Files" in CC preferences.  Once installed I use the update command found under "Help" in the program.  Faster and more reliable.

In Windows 7 

If nothing works for you and you still need to free up C: drive space (SSD?) you might search for info on the "Make Link" command and learn how to use it.  It is a way to move a program from one drive to another and make the OS think it is still in its original place. (Be aware, some files cannot be moved and moved programs will not update.)

If you decide to uninstall it, you will need to undo the MKLINK command (delete created shortcut on C: and copy and paste the program back to the same original C: drive folder first.), then uninstall.  I have uninstalled first and then deleted the program from the other "Root" drive w/o ill effects too.  But I'm no techy, backup everything and create a new "Restore Point" first.