[EVO 4G Android Development] tkirton:
I have to ask you this question: Do you know the difference between Darktremor Apps2SD (also known as Apps2EXT or A2SD+ in the Froyo world) and the Froyo implementation of Apps2SD?

Caukin's rom doesn't have the program that runs the traditional Apps2SD (hence why your EXT partition isn't mounted). I do believe that the rom is geared towards using Froyo Apps2SD.

So, here's the answers to you questions:

1. As long as Caukin's rom supports Apps2EXT or A2SD+ (the name given in Froyo for the traditional Apps2SD such as Darktremor), then you can use Darktremor alongside Froyo Apps2SD.

2. Many Froyo developers believe that the Google implementation of Apps2SD is good enough. The problem that I've seen with the implementation is the following:

a. Incompatible with previous versions of Android: Froyo is the first to implement a FAT32 Apps2SD...if you just happen to go back to Eclair for any reason, your programs are inaccessible. This isn't true for traditional Apps2SD, unless the rom doesn't support script execution (i.e. stock roms).

b. Part of the program is still in Internal storage: From what I've been told, even if you move the program to the FAT32 segment of your SD card, a portion of the program is still left on Internal storage. It appears that Froyo can't directly run programs from the FAT32 part of the SD card and needs some sort of stub-in to make it work. This is different from traditional Apps2SD, which uses a Linux native partition to store the programs, thus allowing direct execution from the SD card.

c. Not all programs can go to Froyo's Apps2SD: Unless you have a third-party program involved, the application has to be written using the latest Android SDK. Programs written in previous versions of the Android SDK will not transfer to the FAT32 portion of the SD card as Froyo will not allow it natively. This isn't true for traditional Apps2SD, since it uses a Linux approach to moving files rather than an Android approach. Traditional Apps2SD sees the program as simply a program.

3. Again, Caukin's rom doesn't have a traditional Apps2SD included. Without a traditional Apps2SD program, you won't be able to mount your EXT partition. This is where there is common confusion between traditional Apps2SD and Froyo Apps2SD. This is why developers started renaming the traditional Apps2SD either A2SD+ or Apps2EXT.

4. Unfortunately, I'm not familiar enough with Spare Parts to give you that answer (my rom doesn't have a Spare Parts program).

It's funny that you mention that nobody replied back to you on your questions for Apps2SD. I have scanned many forums here on XDA and others. This isn't the first time I have seen developers and users ignore an Apps2SD question. I've seen that a lot. I can only speculate why:

I suspect that traditional Apps2SD is rather unfamiliar territory for many developers. Many developers copy an Apps2SD implementation from someone else's rom or, lately, have been using a kitchen program that will create a rom for them with Apps2SD (there's one out there that has Darktremor built into it, but there are others that actually use other implementations). The have it as part of their rom, but they aren't really familiar with the internal working of Apps2SD (and, honestly, it is usually a low priority).

The other suspicion I have is that some people on the forums here would rather answer a complex question than a general question as yours. Their belief is that, because the question has been answered over and over again throughout the forums, they aren't going to answer it because you haven't searched for the answer. The problem I have with that is that XDA is very tedious to search for anything and requires a lot of patience while you filter through messages in threads that don't answer your question. It is easier, at least for me, to answer an already answered question than to tell you to search for it. But, that's just me.