Error with version 5 ##- no space left

Since updating from Version 4.2.2 to Version 5 and above when frame serving using Avisynth and Windows AVFS server I get the error NO SPACE LEFT even though all dics have more than enough space. This does not happen using 4.2.2 and earlier versions. File size, resolution etc makes no difference and it does not matter how much or how little processing has been applied. Preview ( 2 to 10 seconds) works as it should, however when Video AI starts full rendering the error appears very soon after starting.
Link to log files:Topaz - pCloud