In MotoSim you can do it in online function/file manager but the 90's style you'll face with. I worked with KUKA and ABB and both was much more better from this point of view. I got errors when I tried to upload (from pendrive) them back to the controller (where they run before). The problem was that weeks before I started to use alias function and there was some variables which was named (wrongly) before I used alias function. The controller let to run the programs with wrongly named variables but nut let to upload back them. Another error under when upload from pendrive: Not found NOP or END line, but the program was exactly the same what I saved before... I repaired some of the programs, but some of them should be rewrote on pendant.