Table ids are the setup names from the in-game billiards creator (the id in data/billiards.json).
The 3D view shows the real table model. Your felt colour above replaces the table's own felt in the preview. In game, each colour is a different table model you pick when you create the table.
Table models: TayMcKenzieNZ's Pool Tables, converted by BzZz. Tables originally by Rockstar Games. Used with permission.
Drag items on the preview to move them.
Wobble is a random aim error in degrees. 0 is a perfectly accurate cue; a cheap cue might have 1 to 2.
A stand's id is its setup name. If the setup also has a table, the stand id ends in :rack, for example bar:rack. Stands you don't list give the house cue.
The look shows in this preview. In game the cue still uses the script's own cue model, so these colours are for your reference and for a future model.
Unzip it into the as-billiard folder. It contains custom/tables.json and custom/img/tables/ for table designs, and custom/cues.json if you made cues. Then restart the resource.
The layout preview is a stand-in green. If you don't tick "Change the felt colour", the table keeps its own felt and only your logos and text are drawn on top. The 3D view shows the real table with your design on it.