The replay mod is a robust mod/platform but it is in now way a substitution for a full feature editing software like Premier, Final cut, After Effects (if you are J.J. Abrams) or Window Movie Maker (if you are stuck in the 90s). You may find it will take more time trying to create a strong composition working on 1 platform and doing workarounds to get the preferred result, then to split the load between specialized software. If you would like, I can provide links to tutorials on common programs used in video composition.