Press Alt+Click on a key, door, or other object to open up a code editor. You have to set their variables with code to make them function properly, even single keys/doors, or else they break in the editor. How it typically works is you set variables with code formatted like "variable=value;", with the semicolon at the end of every line of code. The most common variables are "count" for key/door count, "w/h" for door width/height, "c" for door lock color, "cs" for door base color, and "type" for key/door type. You can read more about them in the instructions file attached.
Key counters work a special way. Basically, the counter itself is the "list" of key counts to show, and you add the different key colors to that list, which it then auto-generates the counter graphic with. The basic code looks like such "s0=COLOR;s1=COLOR;s2=COLOR;" etc, with each "s" being the first, second, third row of the list (starting from 0), and "COLOR" being replaced with a number which correlates to the key color, which you can find in one of the readme files. You can also set "long=(Either 0, 1, or 2);" to make the counter longer.
