I have both the Casino and Constores OXP loaded and found that they both use the same letter ("C") for Constores and Casinos. This was a bit confusing. So I decided to see how hard it was to change the letter used. Turns out it's pretty easy. Say I want Casinos to be H instead of C (H for Hoopy Casino)
Go to the OXP folder of the item you want to change, Go to the Config Folder, and open the Shipdata file in a text editor. This contains info on the various ships that the OXP adds to the game. Scroll down until you find the name of the ship you want (stationary items like casinos are considered ships). When you find it, look a little further down and you should see a line that has the word 'Beacon' in it.
Just below that line will be a line that says what letter should be displayed in the Advanced Space Compass. It will read something like "C-Casino", Change that first letter to whatever you want for example "H-Casino", and then Casinos will appear with an "H" on your compass.
Pretty easy to do.
You can only use one letter or symbol (it's defined in shipdata.plist with the beacon key - the letter is the first one in the string assigned to that key).
But thanks to a nice little patch from _ds_ that's been in since 1.73, you can also use symbols on the ASC in the same way that you can use them on the HUD for missiles and mines etc. If you have a look at my Fuel Station OXP you'll see an example of it (the icon is defined in the OXP's descriptions.plist by role name, and that overrides the beacon key in shipdata.plist).
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