Yeah quiet around here these last days for a change... !
I finally found the reason why the windows version was slower for scripts, and I have a fix, I sent it by pm to ffman1985 so that he checks it, but he hasn't been reading his messages for 2 days ! Oh well, at least you are in linux, so you don't need this fix, the linux version doesn't have this problem. It's a crazy story about double to int conversions, I assumed they took almost no time with modern cpus, and it's the case in linux, but that's the very reason the windows version is slower, and I can't explain why, but it's a fact. The solution : merge muparser into raine (the doc encourages people to merge it in their project), and change its base type from double to unsigned int. It works, and I finally get the same speed in linux and windows, the only drawback is that float numbers are not recognized anymore in the console but it shouldn't be a problem normally.
I didn't decide yet what to do if he doesn't come back in a reasonable delay to test this, since it's a windows problem only I can just ignore it, or release it without any more testing, or simply commit it to git and start to work on something else. I think I'll probably choose the last option.