Multiple selections in a Trichedit componant

I'm writing a text editor and I really need to select multiple sections
of text within the richedit component the selections do not have to cut
copy or pastable but they do have to be highlighted something along the
lines of Word 6.0 when you misspell a word (the wavy red underline)
would be fine. Can anyone help?

Another problem is a text search tool I have written that causes the
screen to flash while it is working. I'm sure I've seen this problem
mentioned before but I can't seem to find the solution now I need it

This is a final year project for my degree so buying third party
components (unless really cheap) is not possible.

Thanks
M.A.Howl...@Herts.ac.uk