Mark items in CodeCompletion

Good day,
we have been testing quite a long time for the syntax editor and custom list filling options for intellisense. i.e., the implementation of NeedCodeCompletion.

Everything works well, but we have two minor problems:

1) In each row, the first letter is not accepted for the search, just put a space in the row and the search in the intelisense list already works.

2) If I have written some fragmet of text, for example select * from use and I press ctrl + space I would like to mark all items in code completion form containing "use" table name is "users". I press ENTER and "use" replaces "users". This does not work, items with "use" are not marked and after pressing ENTER the "select * from useusers" is added, ie it is not replaced with use. It is possible to modify this behavior somehow.
Hi John,
Both issues might be related to not setting e.StartPosition in handling NeedCodeCompletion event.
I've uploaded a sample project there:
If it does not help, could you send me ( cut-down version of your project where the problem can be reproduced?