Please provide a fully qualified path to those directories.
In the meantime, check it out here: clear-recent-projects-list-in-visual-studio-2015
(1) Please check the following post: set-blobtempstoragepath-and-buffertempstoragepath-to-fast-drives
And try to modify those setting to see if you can set both BLOBTempStoragePath and BufferTempStoragePath point to a different file system location.
It seems that adding more RAM to the SSIS server would be helpful. It will prevent swapping from memory to a file system.
(2) .nlp temporary files are created by the .Net Framework 3.5. When you will upgrade your SSIS packages from 2008 to 2019, Script Task will use .Net Framework 4.* Thar version of the framework doesn't create such temporary files.