Having worked an awful lot with the Platine paper (is that what you are
using?), I would recommend trying two things either seperately or together.
1. Try adding 2 drops of glycerine to your sensitizer.
2. If you are using a sloppy wet coating of sensitizer, get it onto the
paper quickly and evenly and then lift the paper up by one corner and
using a sharp jerking motion shake the paper up and down so that the
sensitizer begins to "run". Then grab another corner and do the same.
repeat with all for corners. This tends to even out the coating. You
can also set the paper up on edge until it has a matte finish (and then
dry), or you can hang it by a corner.
Best of luck,
David