Hello Frank,
I just did what you asked and I confirm it's working again like it should. Thank you so much!
Can I keep using this version and wait for the next release in which this will be solved?
By the way: it also solved another bug. 1.9.3 did not like the other plugin to rewrite the CSS url's. As a result they were not combined properly. Some CSS files were not being included in the combined file. After your fix they are combined properly!
Thanks again!
Rick