HI.
Here's something I hope you will find useful. Here we use the Low Pass bitmap filter to smooth, and thicken or thin a design.
~John
http://community.coreldraw.com/cfs-file.ashx/__key/CommunityServer.Discussions.Components.Files/704/3527.gdg_5F00_tips_5F00_tricks_5F00_1_5F00_using_5F00_low_5F00_pass_5F00_bitmap_5F00_filter_5F00_to_5F00_thicken_5F00_artwork.swf