a screen shoot would help to understand the problem.
When you say "only 2 PCs show altered Design" did you check on the SAME PC 2 users 1 works and the 2nd doesn't? the SAME user observe the same altered Design on 2 different PC.
if yes the problem is not in the PC but in the design of the mailbox. If you have a lotus Admin contact him and tell the mailbox need a "refresh design" and/or is altered and need a "fixup".