This guide was the last in Technical Guides @RDD and was also made at a time when PvP Dimensions were still very new. Tooltips have changed so they are straight forward however with Alfiexx you'll also see:
Using the Dimensional Indicator
Invisible wall possibilities
Using items for non PvP Dimensions (ie Puzzles, Mazes, Haunted Houses.)
PvP Dimensions 2015
PvP Dimension items are not available via Minions so you will find them on the Rift Store where the key to Black Garden is available through Starter Packs and has a max capacity of 2520.
There are also PvP items available spending favor in Tempest Bay with PvP General Goods NPC "Mercenary Hudson" (12989, 11708)
NB: PvP Dimensions currently do not have leadership boards and also do not provide gear bolstering as shared by Pithos Rifts Lead Engineer March 2014.