Answering my own question.
PPL please read the doco first
there is answer to my question right here:http://documentation.red-gate.com/display/DM2/Variables
To stop polluting system temp folder (and control free disk space) on the agent machine someone can define variable RedGatePackageDirectoryPath
to point to some custom temp location. That is what we did and faced the problem described in original post.
To address clean up issue in custom temp there is another variable: RedGatePurgePackageDirectoryBeforeCopy
. Set it to True
and agent will clean the folder before copying files into it.