We saw this at the LA premiere last night, complete with cast and crew (and their families and friends, which made for an enthusiastic and fun audience).
Even with 10X the budget, it still had the no-expense look. All the old characters were back, including the bickering aliens Kro-bar and his wife, dead characters resurrected as their not-so-evil twins, and yes, Animala. Of course the Skeleton is back, although only as a skull (which gives him certain dependency issues). He gets the best lines (while waiting for his minions to carry out some task - "It's the waiting that's difficult").
All the performances were excellent, particularly Larry Blamire as the bitter scientist (another scientist took credit for his rock) and wife Fay Masterston.
The plot, such as it is, involves a race to South America to obtain the valuable Geranium-90, worshiped by the Cantalope people. It's basically 60 minutes of plot stuffed into a 90-minute movie. Although the individual jokes are often very funny, the framework is too bare-bones and linear. Even cheeseball 50s SF movies often had, you know, subplots. There's a lengthy middle section where everyone passes the same banana plant about 10 times (which was probably part of the joke). Failing a bit of a rewrite and reshoot, editing down to 70 or 75 minutes would help.
To his credit, Larry Blamire said he would not do another sequel, as he fears the jokes would start repeating themselves. True enough.