Depends which placeables hak your are trying to use and in what way it is not compatible.
You will at least need to get placeables.2da right. There will be one in the placeables hak and if it's out of date it won't have the entries for the patch 1.69 placeables so you will need to do some merging. If the placeables hak author assigned row numbers that don't conflict with the ones BIoware used for 1.69, you're in luck - you can merge the two 2da files. If they do conflict, you will have to assign new row numbers to the hak placeables and then modify the templates that reference them to use the new numbers.