It's basically the same steps as above. Each install.wim for the Enterprise editions only contains one single image, so it's basically just modifying the command examples given for the Enterprise editions.
So, assuming I have the x86 Enterprise DVD copied to e:\entx86 and the x64 Enterprise DVD copied to e:\entx64 and I want to combine these into an AIO destination of d:\aio, the commands would be:
For x86
imagex.exe /export e:\entx86\sources\install.wim 1 D:\aio\sources\install.wim "Windows 7 ENTERPRISE x86"
For x64
imagex.exe /export e:\entx64\sources\install.wim 1 D:\aio\sources\install.wim "Windows 7 ENTERPRISE x64"
These examples are just specifying each version of the Enterprise install.wim as source, specifying image index 1 as the image to export (as the Enterprise ISOs only have 1 anyway) and specifying the AIO install.wim destination to export to.
My disc gives me these options:
(2nd shot to show Enterprise editions as the list is too long for them all to fit in one image)
Also yes, x64 Home Basic is a weird one. It doesn't look like it's going to be sold and nobody appears to even acknowledge its existance but it is clearly on the x64 DVD - you can see "install_Windows 7 HOMEBASIC.clg" in the sources folder and you will get the ability to install it if you remove ei.cfg.
It definitely installs fine both integrated into an AIO image and also by simply using an untouched image with ei.cfg removed:
So while it does work, seeing as this version seemingly won't be sold it was probably pointless integrating into the AIO image. Ah well, it didn't really make any difference to the ISO size