Hello,
If the module is working as expected, both checkboxes should do, what their name says:
createVersion
If True and an asset with the specified name exists, then Experience Manager creates a new version of the asset.
replace
If True and an asset with the specified name exists, Experience Manager deletes the asset then re-create it.
If the asset exists and neither createVersion nor replace is specified, then Experience Manager updates the asset’s current version with the new binary.
Regards
Lars