ClamWin uses the scan engine and virus database provided by the Clam AV project. All false positives should be reported to Clam AV via their web page at http://www.clamav.net/contact
on the web (be sure to select the false positive reporting option).
However, Clam AV has a policy of not correcting false signatures on PUA. PUA is an optional detection. Many Clam AV PUA signatures are made on packers and installers--which can be used by both goodware and malware. So you will save yourself a lot of grief by getting rid of the --detect-pua configuration in the command line block on the ClamWin Advanced tab.