Undead Anatomy 4 missing abilities?

[LearnTheRules]

Ok so I may be missing something here, I'm in the middle of building a shape-shifting wizard who will take almost all the polymorph spells .

I came across one thing which got my attention while looking through the Undead Anatomy spells. While the higher level ones do say that they count as the previous level (and by extension any level under that), some of the abilities assumed are in mentioned in the previous spell, making me confused as to whether or not you can also assume the abilities given in the lower level spells' lists.

To give an example, Undead Anatomy 3 can get rake, but it is mentioned again in Undead anatomy 4. However blood drain is not in either of these lists.

Does this mean that you can only choose from the abilities given in the list of the spell being cast?

Say I'm casting UA 4 to turn into a vampire, which does not have blood drain on the abilities list, yet supposedly counts as all the previous levels of the spell chain. Do I get blood drain or do I only get fast healing 5 and the DR 10/magic and silver from the 4th spell level list?

[Skylancer4]

Not having the spells to look at, I do know that sometimes there are limits on particular abilities (notably speed).

[Are]

I would assume the intent is that you'll get the abilities from the lower level spells as well.

[LearnTheRules]

Here

I'm also thinking that was the intent, after all you get the fiery skeleton abilities from the the 4th spell but wouldn't have DR 5/bludgeoning. It's just poorly worded or else actually missing stuff it should have; the superfluous abilities make me wonder :-/

[Skylancer4]

If you notice wording, it states specifically if the form you poly into has the following abilities you gain them. However each spell has a size range (except 4) so apparently each spell is limited. S/M has abilities in spell 1, T/L has to choose abilities in spell 2 BUT you can do spell 1 still too, D/H has to choose abilities in spell 3 but can still do forms from spell 1/2. Spell 4 gives a list of better abilities available period.

At least RAW that is how it reads, intent who knows.

[LearnTheRules]

Having looked at other polymorph spell chains, I believe they were meant to be written as the Plant Shape ones. You get all the abilities from the previous versions, which are listed superfluously in all the other polymorph spell chains, such as Beast Form and Undead Anatomy.

The druid guides in the advice subforum helped clear this up. I found the spells poorly worded and seemingly contradictory, but Plant Shape is probably how they were meant to be written. No abilities from lower levels are mentioned in the list, making it implicit that you are supposed to get them from the higher levels.