I am using the default party for MM2. When I level my Sorcerer to level 2 my max SP decreases from 7 to 3. Is this a glitch of some kind? I have tried restarting and leveling again but it's always the same result.

What's her intelligence?

(Note that resting will cause SP to be recalculated; this might fix your issue.)

By the way, I don't like the default party because it doesn't have enough female fighter types; assuming you want the same party makeup, I recommend either making the Knight female, or both the Paladin and Cleric female (and give your new Cleric more speed while you're at it). (I am actually being serious from a gameplay standpoint; there are actually enemies that male characters can't hurt physically (and the same for female characters, though the ones with male immunity seem to be more prominent).)

Intelligence is 21. I tried sleeping but nothing happens. I also tried training in Sandsobar instead with the same result.

It's very odd. And it goes down as soon as train. The starting INT for level 1 is 7. Then when I train it drops to 3.

Ok, so I created a custom party. Once again, my sorcerer's SP goes to 3 from 7 when I level up to level 2 even though his INT is 20. There seems to be something hard coded about this. Every sorcerer leveling to level 2 drops to 3 SP rather than gaining SP.

What happens at level 3?

A level 3 SP increases to 6. So for some reason it seems to reset my SP to 3 and then give me the minimum every level after that.

Someone really should have asked this question before, but what version are you playing?

(With CRPGs this old, it is my experience that different versions on different platforms have different bugs.)

Just the one I downloaded from GoG. Do they have multiple versions?

Where do I find what version it is?

It's the PC version you have. Dtgreene was wondering if you're playing a NES version for example.

It's a strange glitch you're describing. If you have the time. Can you try a sorcerer whose INT is not in the 19-21 range? So get a sorcerer with, say, 18 INT and see if he gets 6 SP at start up and another 6 at level up.

These are the SPs you're supposed to get per level
(first colum shows PER/INT attribute, second column SP per level. The forums don't format tables really well here).

----------------+------------------+--------+--------+
13-14 | 4 | 1 | 1 |
15-16 | 5 | 2 | 2 |
17-18 | 6 | 3 | 3 |
19-21 | 7 | 4 | 4 |
22-25 | 8 | 5 | 5 |
26-29 | 9 | 6 | 6 |
30-44 | 10 | 7 | 7 |
45-59 | 11 | 8 | 8 |
60-74 | 12 | 9 | 9 |
75-89 | 13 | 10 | 10 |
90-??? | 14 | 11 | 11 |
----------------+------------------+--------+--------+

1. Please don't capitalize my username, even if it's at the beginning of a sentence.

2. There isn't an NES version of MM2. There is, however, a SNES version; actually, there's two of them, one released in Japan and one released in Europe. I'm not familiar with the Japan version (I've only seen screenshots), but I have seen enough videos of the European version to know that it is badly broken and should be avoided. (Apparently, they were planning on releasing the version Europe got in the US; I have a feeling it was cancelled because they couldn't get that buggy mess of a game past Nintendo of America's QA.)