[MonoDevelop] installed package not running

[Bric]

OK, putting my git compile effort on pause, I apt-get installed what's 
currently available:

apt-cache policy monodevelop
monodevelop:
   Installed: 4.0.12+dfsg-2
   Candidate: 4.0.12+dfsg-2
   Version table:
  *** 4.0.12+dfsg-2 0
         500 http://us.archive.ubuntu.com/ubuntu/ trusty/universe i386 
Packages
         100 /var/lib/dpkg/status

But when I run it, I get:


Unhandled Exception:
System.TypeLoadException: A type load exception has occurred.
   at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) 
[0x00000] in <filename unknown>:0
[ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: A type load 
exception has occurred.
   at MonoDevelop.Startup.MonoDevelopMain.Main (System.String[] args) 
[0x00000] in <filename unknown>:0


________________

Is it, by chance, because I have a mix of locally built mono (latest 
git) and libmono lib from the repository?  (Is the package trying to 
include my local build?)

thanks