/p option doesn't work properly, Plextor drives can rip only the -75, -1 range of the first pregap directly. It's somewhat hard to explain the correct method to dump properly the first pregap when this one contains actual audio data (the miniCD Audio disc bundled with Tenbu MegaCD Special, for example), but would something like this.
-Read the -5000,-76 range, D8 command of couse. When reach more or less the -1000 LBA will report many read errors, it's normal and expected.
-A part of the lead-in, the entire first pregap and a piece of the first track, index 1, is dumped.
-Then use the first sectors of the normal dump to search them in the dumped file, find the portion which matches those first sectors and extract the previous 352800 bytes into a separated file.
-The subcode is easy, just extract into a separarated file the frames with 00:00:00 - 00:01:74 AMSF.
http://www.mediafire.com/?470d0r269wg6bce
I have uploaded a sample, the entire minidisc and the pregap extracted as I have proposed via the audio option.
Then, I have hashed the first 75 sectors of the first track and these ones are the results. Program used is parthash, much easier than cutting the dump and whatnot:
/viewtopic.php?t=8828
D:\MiniCD\Main dump>parthash "MiniCD (Track 1).bin" 176400
# Size CRC-32 MD5/SHA-1
1 176400 fa5fa23f 4e9bff8a8ab29fafb6252977de6b11ea
714a04d835419264528b0327c143de4267e3d961
2 39588864 e0c9e590 4083df206ba8ab18864aa27590ac346c
dc47b01492f14f26b60bccd4de635d016a2b239d
Then I run the findcrcs.exe program by V. in the lead-in+first pregap+a piece of first track dump and these are the results:
D:\MiniCD\Pregap>findcrcs Pregap.bin 176400 FA5FA23F
4290048 fa5fa23f 4e9bff8a8ab29fafb6252977de6b11ea
Thus 4290048 is the starting point of the main dump, so I have to extract 3937248-4290047 range into a separated file to have the actual pregap ripped once and for all. The subcode is easy, just delete everything except the range with AMSF 00:00:00 - 00:01:74.
findcrcs.exe program is here, including source code.
/viewtopic.php?t=8348
With these suggestions, perhaps you can implement a proper routine to extract properly the first pregap of these discs.
And it would be cool to implement another routine to extract the lead-out of certain discs which contains audio data in the lead-out. My Alanis Morissette - Jagged Little Pill [UK(9362-459012)], as far you remember you purchased this one to perform certain tests related to the slowness when ripping discs with R-W filled with 0xff, contains data in the actual lead-out, so could be useful to implement an option to rip into a separated file the first 100 sectors of the lead-out, applying either the offset correction autodetected by D8 (if disc contains a data track, Heavy nova for MCD for example), the standard one of AccurateRip or the overriden by the /a parameter.