You are using the v0.6 test version, right?
Yes, MG 0.6. I did the die($updateQueryString); and looked at the query and all looked correct, the field names and the content of the custom fields was included and are correct.
UPDATE `mymodx`.modx_maxigallery SET title='this is the title', descr='description here', author='Author Name', tags='1,2,3,4', pos=1, hide='0' WHERE id='2'
I manually entered the data in the database but it did not show on the manage pictures page.
Here is the call, nothing fancy:
[!MaxiGallery? &pics_per_row=`5` &max_thumb_size=`160x200` &max_pic_size=`0` &customFields=`author,tags`!]
The placeholders for the data I entered manually are outputting the correct data in the galleryPictureTpl. It seems to only be the update issue. [+maxigallery.picture.author+]