Formats portability matrix:

Classic trackers: trackers with classic formats, mod, s3m, xm, it

Modern trackers: more recent trackers with different formats, like renoise

                   Portable   Can be considered portable format
_________________|__________|__________________________________
Classic trackers | Yes      | Yes
Modern trackers  | Some*    | No
Complex DAW      | None     | No


Non-Portable features of modern trackers/renoise:
- internal plugins
- external plugins...
- plugin instruments
- the format is not specified generally
- usually too complex / complicated to be portable / dependant on OS/implementation
- no third party players
- no third party imports etc
- only one implementation usually
- overall not very portable / limited portability