My expeience with plastic molds and cold process hasn't been real good. It seems to like to stick real bad, and when I do get it out some of the soap pulls away and was left in the mold.
You might try greasing it real good with mineral oil "same as baby oil" and let it sit in there for a few days then freeze it overnight. Work the sides away from the soap very slowly and work some pressure around the bottom untill it releases. A mold with a tapered shape is better.
Also trimming the plastic away close to the edges of the mold help to pull the sides away easier, because then the mold isn't so rigid because of the 90 degree angle.
I see the instructions say to freeze, then dip in hot water. That beehive looking mold looks like it might work out OK.
I have several Milky Way molds and use them for cp all the time. It just takes a bit more of a cure time to get them out. I use them alot for when I have a bit of extra soap left when soaping. It seems too that once I "seasoned" my molds, the easier it is to get soaps and my bath bombs out.