WZ No Access to Memory Location

That's definitely a new one, never had that before. To what extent did you copy or import, and how recent is KMS 1.2.65? If it utilizes a lot of new properties, something internal with how maps work pre-BB could have recently changed in KMS. That, or there's new nodes you need to remove/handle in order for them to work. I'd compare current v83 maps to ones in KMS 1.2.65 and find differences to see what all they had changed and/or done differently.

KMS 1.2.65 isn't very recent, content-wise it is somewhere between GMS v62 and v83 (no Aran or Cygnus yet). Using WzRepacker I copied over the map .img files (and removed nodes that KMS 1.2.65 does not use), backgrounds, reactors, obj, and tiles. Some maps I am able to see the tiles/background for a split second before I disconnect instantly, but I am not sure what relevance this has. In case mobs or npcs may be affecting the issue, I have been testing with maps that do not have either of these. The result is the same.

Is it possible that using the copy/paste function of WzRepacker is not working properly when copying over from wz files that have a different encryption? Earlier, I was copy/pasting GMS UI.wz files to translate some KMS UI elements that were in Korean, but I found that doing so froze my client. Later on I learned that if I exported all of the .png files from the GMS UI.wz, then manually imported them one-by-one using the "Change" button in WzRepacker, the same GMS UI elements would miraculously start working in the KMS client.

In terms of importing maps, I started wondering if I would need to import the .png files from the GMS wz files separately, just like I did with the UI.wz files. Any insight about this?