fight_ar.cts and fight_pr.cts contain the coordinates for each fighter. Anytime you want to change any positioning for a mod, always look for a corresponding cts file to the table or lua file you're editing. You can edit these in notepad just like any table file. The format of each entry is <x z y>. You can use the osd of Powertools to get your current player positioning and use that info to change them.
Inside fight_ar.cts, some further info:
fight_ar_start <- coords for host start
fight_ar_remote_start <- coords for remote player start
fight_ar_end <- coords where host is dumped after activity
fight_ar_remote_end <- coords where remote player is dumped after activity
fight_ar_$c000 <- coordinates for first fighter
For even more fun, you can change the map icon and start location of the activity itself too by editing activity_start_sr2_city.cts. The two entries that define that are:
activity_start_sr2_city_fight_pr
activity_start_sr2_city_fight_ar
One thing I like to do while testing mods is move their start locations inside a crib so I can easily load a save then immediately launch and test.
shops_sr2_city.cts has coords for the lightcone triggers for all the shops. The way to find out the spelunkers info is to first open shops_sr2_city.xtbl and find out what the trigger names are. I searched on spelunk within that file and easily found the "CV Gift" entry (likely abbreviated for cavern giftshop.) The <Shop_Trigger> info is what we want, and it's listed as "shops_sr2_city_$CV_gift_store". Armed with that info, I search in shops_sr2_city.cts and find that entry with the coords of <-1165.340820 -1.436431 721.971008>. These are in xzy format, so adjust accordingly with new coords from Powertools.
Also, be careful with adding to inventory. You've got the right table (customization_stores.xtbl) but there are a limited number of entries you can have for each store and additional ones past that simply won't appear in that store. You definitely will not be able to have all clothing available in only one store if that's what you're looking for.