1) Does TORTOISE run on all operating systems?

-- TORTOISE currently runs on Linux and MAC. Unfortunately for the moment we have discontinued the support for windows. If you do use Windows 10, TORTOISE can be run using the "Windows 10 Ubuntu subsystem".

2) How different are the versions 3.0 and above of TORTOISE compared to 2.5.2 and below?

-- Versions 3.0 and above TORTOISE modules can be run from command line. This enables batch processing and command scan be easily incorporated into scripts without the interference of IDL gui as with previous versions.

3) Have lot of features changed between the IDL version and the new command line version of the software?

-- A few additional features have been introduced in the versions 3.0 and above, such as gibbs ringing correction, denoising,  ANTSsyN EPI correction in DIFFPREP, additional features in DRBUDDI etc.

4) Can you combine processing from two different versions of the software?

-- We highly recommend not combining processing results from two different versions of the software.