Saving maps taking forever

Hello everyone.

I’ve a problem with some maps of my project: I’ve set up it to have only real time lighting [ “Force No Precomputed Lighting” ] and rebuilt my map. First of all, it’s size doesn’t decrease. In second instance, from time to time, it takes something like 5 minutes to save these maps, with the progression bar freezed on “Compressing texture_2d_####” : this seems to me like a lightmap, that for some reason is still in the map.
Many times, it takes only two seconds to save. File size is around 88Mb.
It’s quite annoying, cause I’ve to render out some matinee’ sequence and I’m wasting a lot of time just watching the progress bar…

Any suggestion? I’m doing something wrong?