I was going to make an article of this, but I think I'll just get straight to the point.

As many of you should know, CTF levels should have a mask placed around them to prevent flag bug. The problem with this is that when testing the level in jcs the tester will be stuck in the upper-left hand corner. Some reviewers advise you to put a single player start position in your levels. I reccomend that you do not do this.

When putting a single player start position in a ctf level (wich should be using MP starts), I have observed that both teams may occasionally start there in multiplayer. This creates balancing problems and can ruin a level.

A better alternative to putting a single player level start in a CTF level is to make a small room at position 5,0 and place a warp going into the level. When testing in single player, the position 5,0 is the default start position if there isn't an event for it in the level. Players will not spawn there in multiplayer, so this method will not mess up gameplay. Cell has already demonstrated this in many of his levels, and I think you should all copy him and make it easier for level reviewers.