no need to apologize... getting patches into Wine is always a bit constrained because of ensuring that we mimic Windows' behavior... and cmd is even more combersome as testing cmd is even more constrained
for testing, you can subscribe to testbot.winehq.org (there you can test on several windows versions)
I recommend if you can test first locally (your Win10 setup is a good choice), then run the changes in testbot for all default test env (anyway the patch will be tested in the integration pipeline against these, so better test in advance), then update the MR...
concerning your failing code, you could use:
```
cmd /c `block_if_eof1.cmd`
```
with a comment explaining why you need to enclose the test inside another instance of cmd
(and I don't thing there's lot of value to check %errorlevel% upon cmd exit)
--
https://gitlab.winehq.org/wine/wine/-/merge_requests/4168#note_49967
typelib has an array size of 2 (eg LibXml_Last), so a lookup
of IID_NULL will result in a lookup of the third index.
--
v6: msxml3: Do not leak bind context on error paths (Coverity)
https://gitlab.winehq.org/wine/wine/-/merge_requests/4073