django-modeltranslation bug not support custom field

[Biftor]

Hi,
First of all appreciated to adding support for this package (from here) with great UI.
There are couple of issues/bugs may need to mention to figure it out somehow,
it seems you have added support this style

for some specific fields like charField or textfields, not for every cases which a field is translatable.
for example if i extend textfields to some other classes name(in my case MaxLengthTextField), the style not working as you see in screen shot

also not support image fields or file fields, in case you have them translatable

Thank you for your great work.
Regards,