Different jpg-output on Win7- and Linux-machine

You’re using two different versions of RawTherapee, so you will get different results if you use the tools whose code has been changed between those versions. Furthermore, both of those versions are very old and not recommended. Get a more recent development version, 4.2.1000 or higher.

By using the same version. 4.2.1148 in Windows will give the same results as 4.2.1148 in Linux.