Yes, the syntax highlighting engine of UE/UES does not support regular expression definitions for highlighting making such special highlighting requirements sometimes impossible. I can give you no advice how to solve this syntax highlighting problem of UE/UES for this Delphi language special because I could not find a solution. I can only suggest not to use {...} for block commenting which is probably inacceptable for you. Only possible is to define (* and *) as block comment strings and { and } as alternate block comment. Alternate block comments can be highlighted with a different color. That could be used to highlight compiler directives {$...} and of course block comments using {...} completely in a different color.

delphi1-8(dotnet).uew seems to be very old. Therefore I had attached (already deleted) to this post a hopefully improved version. I don't know much about Delphi nor do I have example files. So please tell me if my version is better and if IDM should upload this version to their server.

Block Comment On = {$ Block Comment Off = } Block Comment On Alt = { Block Comment Off Alt = }

would work and favor highlighting of compiler directives over block comments. But line comments, alternate line comments and block comments are all highlighted with the same color and therefore I think this is no help for you.

The problem you have with highlighting := is probably caused by bad delimiters. Use the attached wordfile which contains all your words and all your color and font style settings and those setting lines created by mistake deleted.

The only chance to get compiler directives not highlighted as block comment is to use for example always {! or {# as block comment starting string in your Delphi source files and specify this string as block comment on string. That is definitely not the best solution, but would be a helpful workaround for this syntax highlighting problem with UE/UES.