Conflicts with other addons aren't necessarily a bad thing, it just means that in the case of conflicting addons, the file in question with the same name will be used (in the first addon that loads) while the other addon's file is ignored entirely, as long as it's within the same file path.

By subscribing to both fixes first, then subscribing to the original Helm's Deep Reborn, the fixes will get applied first, while the Survival Map's files are ignored. This ensures that the fixes will take place every time and that you can play the map unrestricted.

Alternatively, you can get any main menu addon you desire, then subscribe to the two fixes. This also ensures that Helm's Deep's malicious changes to the Main Menu doesn't take affect on your game.

The order in which you subscribe to ALWAYS matters. I trust you, as the players of L4D2, to use this information to your advantage.