As given in the custom test type APIs
I have registered the test type and remote agent dll.
Signed those files, had them listed in the INI file. Made a cab file and put that in the extensions directory.
Bit after re-deployment i my new test type is not appearing in QC.
On checking the log files i got this error :
"Unable to create instance of test type: XYZ, of GUID: caf137a7-a40a-33b0-99f6-4b91536418b9."
Any help in this regard is much appreciated.