Do you mean that the tests pass on Windows but not Wine when using load_v6_module, or that they don't pass on either platform? I used load_v6_module for some v6 imagelist tests (which may not yet be merged into Wine actually; I should probably check that and resubmit) and they worked fine. You may want to look at http://tinyurl.com/ybo28lt for instance.
If the tests are working on Windows but not on Wine, the obvious reason for your tests failing would be that the required alpha channel support is not implemented.
Cheers,
It sounds like I need to investigate further, but no - I'm only talking about Windows. With crosstest, load_v6_module seems not to switch to v6 with regard to image lists.