Your Windows user-name is 'Kazım' - I assume you are perhaps Turkish ? That is an 'ı' not an 'i' ? In earlier versions of SketchUp using a non-ASCI character in a file or folder path was 'fatal', but in newer versions this can be avoided if the script's coding 'forces' the passed path to a file or folder into an acceptable UTF-8 format... So I suspect that this particular extension has failed to do that step. Contact the author and point out that his current code fails to encode strings for file or folder paths properly as UTF-8. It is a relatively easy fix [at least for the newer SketchUp versions]...

Maybe a late answer but have you look at the RAM usage? Displacement eat a lot of memory and since I started testing displacement my ram usage use to go up to 95% and CPU to 20% and then I have 16 gb ram. That is a model of 40 MB, with a mush bigger model and some displacement it is sertanly ram usage that slows down the process.