when I tried to apply a control line to an image, an error message was shortly displayed at the upper screen edge - too short to read it completely, but it started with “Internal error - correction field …”. After a very short time, the error message vanished again. No control line was added to the local adjustments.
After a few tries, it was finally possible to add the control line.
Regardless what the cause was, any error message should at least be shown long enough to be read.
You (and DxO technical support) can probably find more details about the problem in the log files. On Windows, these are in the user’s Documents folder in an appropriately named sub-folder.
This is a known issue which is actual for PL5.0 as well. To avoid it you should switch off the mask display as a workaround while we are working on the fix.