I use this for my absolute top 3 fave servers for HL2DM and thought I would share it. If you want you can easily add more but remember when adding more servers to the top to re-number all the entries beneath.
Firstly open the gamemenu.res with notepad or wordpad. (I prefer wordpad it looks better, sometimes notepad has all the commands on one long line.)
All you need to do is add the correct IP addresses and if needed a password also to change the "label" so it makes sense to you, when all that is done paste it into...
C:\Program Files\Steam\steamapps\SourceMods\gesource\resource.
Download Gamemenu.res
here right click save as.
Pics to show how it looks at menu and when ingame.
My HL2DM start menu.
Not limited to just joining servers, you can use it to exec config files.
"command" "engine exec keefy.cfg" //this executes my cfg file, you do not have to add the .cfg if you don't want to it does work without.
Yes I know quit is spelt wrong in the picture above, type quti in the console next time you play CS:S or HL2DM
Any problems please post.