Removing some unnecessary changes and making new tweaks in CDD
to move forward with a solution towars working dbj/CDD checkboxes in repeatgroups.
changes in CDD are solving the issue described earlier this way:
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Now we have 5 tables involved

chb_test_c1 - main
chb_test_c1_21_repeat - autocreated when group set to repeat
chb_test_c1_21_repeat_repeat_MKOOD - autocreated when dbjoin dropdown changed to checkboxes
chb_test_c1_21_repeat_repeat_OKOOD - autocreated - CDD changed to checkboxes. Watches MKOOD
chb_test_c1_21_repeat_repeat_AKOOD - autocreated when CDD(checkboxes) element was created inside repeated group. Watches OKOOD
When submitting data and seeing it in list view everything works almost like a charm.

BUT I cant open form to edit it or details view when OKOOD watches MKOOD :
Unknown column 'Array' in 'where clause' SQL=SELECT DISTINCT(`chb_test_c1_21_repeat_repeat_OKOOD`.`OKOOD`) AS value, `chb_test_c1_21_repeat_repeat_OKOOD`.`ONIMI`AS text FROM `EHAK_OV` AS `chb_test_c1_21_repeat_repeat_OKOOD` WHERE MKOOD IN (Array) ORDER BY text ASC

NB! - when the group is repeated twice then the condition looks like IN (Array,Array).
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