Not a bug
BYOND Version:493
Operating System:Windows Vista Home Premium
Web Browser:Firefox 7.0.1
Applies to:Dream Maker
Status: Not a bug

This is not a bug. It may be an incorrect use of syntax or a limitation in the software. For further discussion on the matter, please consult the BYOND forums.
Descriptive Problem Summary:
Ever since BYOND 455 the map editor has been bugged. And after downloading the latest version just now, its STILL bugged!
Whenever you flick between the Z levels on a map, there is about a 10 seconds delay/lock-up that simply IS NOT there on 454 or earlier.
It's also ridiculously laggy when trying to simply edit the map.
I'm suprised this huge bug has gone unfixed for so long.
~ Please note that this is only on larger maps; that's not to say it's "my fault for having such a large map" because its not. Like I said, it works just fine on 454.

Does the problem occur:
Yes, 100% of the time the map editor is laggy.

When does the problem NOT occur?
When you have a tiny map.

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked?
Make a small map or have BYOND 454

This has been a serious headache for me and the bane of my life re: BYOND.
Could we please take it seriously this time and not just file it under ignore. :)

This isn't a bug. It's just a change to the drawing code that unfortunately takes a toll on bigger maps. Obviously we'd like to improve on it, but this has been brought up before and is not a new issue.
:\ Can we not just have a toggle option/setting for isometric type maps, then?
Or perhaps .dmm for maps and .dmsomethingelse for isometric maps?
The entire drawing code changed; the issue isn't that isometric maps can be used, it's that the old drawing code which had some serious drawbacks was completely replaced.
Oh I see; I have an ATI Radeon HD 5670 (1GB gfx card) but only 2 GB of RAM and a 2.4 core 2 duo.
With an upgraded computer, would I see less map editor lag? If so, would it be the RAM or CPU that made the difference.
I remember when I first mentioned this problem and the best response I got was upgrade yor video card (which I have since done with no improvement at all btw).
OR is the lag inevitable for now?
It may be inevitable for now; smaller maps will make a significant difference, since it comes down to how the world map is drawn.