Any comment is welcome

1) why a switch in the header file, why not a "header file converter". The likelyhood that you, should you switch compiler, will not do anything but call another .exe is virtually zero.
2) #ifdef #if are not 'helpers', they are 'unavoidable nuisances', the more you have, the more unreadable your code becomes.
3) all this is good and well, but I, for one, DETEST the 'standard' SFR files. I can not count the number of times I have found a bug in someone elses program that was hidden because a bit was changed both as a bit and as mov SFR,#.
4) SFR16 is the death of many efforts. E.g. for the PCA the sequence of writing high and low is critically important, how do you propose handling that for requirements that vary (some A/Ds require the opposite?. Also, some compilers require SFR16 to be to adjecent SFRs, I believe yours do not. I suggest you get rid of SFR16, it is a trap and those that 'need' it should not be programming in the first place.

I know you produce a free tool, but why not aim for a professional functionality/appearance.

Erik

Again, although I have absolutely no interest in them, I laud your efforts.