OK, after reading Charles's post, I went and looked into this again.
My problem is/was that I could not even create a MIGXdb to begin with. After clicking "Done" in attempt to create my first MIGXdb, the error message "quip.thread_err_save" immediately pops up and I was stuck.
I was a little more reasonable today and had a wisdom to look into modx's Error log (really!)
here is what I saw.
[2013-04-19 14:02:20] (ERROR @ /assets/components/migx/connector.php) Error HY000 executing statement:
INSERT INTO `modx_migx_configs` (`name`, `formtabs`, `contextmenus`, `actionbuttons`, `columnbuttons`, `filters`, `extended`, `columns`, `createdby`, `createdon`, `editedby`, `deleted`, `deletedby`, `published`, `publishedby`) VALUES ('activity', '[]', '', '', '', '', '{\"migx_add\":\"\",\"formcaption\":\"\",\"win_id\":\"activity\",\"multiple_formtabs\":\"\",\"packageName\":\"\",\"classname\":\"\",\"task\":\"\",\"getlistsort\":\"\",\"getlistsortdir\":\"\",\"use_custom_prefix\":\"0\",\"prefix\":\"\",\"grid\":\"\",\"gridload_mode\":\"1\",\"check_resid\":\"1\",\"check_resid_TV\":\"\",\"join_alias\":\"\",\"getlistwhere\":\"\",\"joins\":\"\",\"cmpmaincaption\":\"\",\"cmptabcaption\":\"\",\"cmptabdescription\":\"\",\"cmptabcontroller\":\"\"}', '', 1, '2013-04-19 14:02:20', 0, 0, 0, 1, 0)
Array
(
[0] => HY000
[1] => 1364
[2] => Field 'editedon' doesn't have a default value
)
It showed the mysql operation did not go well when attempting to write to 'modx_migx_configs' table.
I logged into the database using phpMyAdmin, went into the table and modified "editedon" field to accept null value.
After that, I tried to create and save migx again. Same error message pops up, the Error log was the same except for this line
[2] => Field 'deletedon' doesn't have a default value
repeat the same process to modify "deletedon" field in mysql and
[2] => Field 'publishedon' doesn't have a default value
repeat the same process for the third time and I was finally able to make a MIGXdb for the first time.
Charles talked about changing schema. I think this is so for consistency purpose (which I did on /core/components/migx/model/schema/ although I do not know if this is the right file)
I still dont understand why I had to go through these extra steps to make the things work. Obviously the majority of people did not need to go through this. However, going through the forum posts, I have found this
https://forums.modx.com/thread/?thread=58462&i=1&page=4
The last post from lithiumlab basically describes my fix, although he was applying this to modx_quip_comments table