When installing several swf mods in the SDT the game begins to slow down.
Flash is a low-performance platform which cannot effectively optimize its graphics. The result is that each additional sprite shown on-screen
will slightly degrade the game's performance.
There are various techniques for managing this
problem such as: close background applications, reduce the size of the game window, reduce the game's graphics quality, disable strand shaders, disable spit strands, don't use bukkake mode, use static hairstyles instead of dynamic ones, use an older Flash Player version, upgrade your computer, etc.
If you're using sby's moreClothing mod and loading hundreds of files during startup, then you should be able to improve performance by culling your list -- remove some of the rarely-used files and retain only the ones which are most important to you.
Please someone tell me what I can do to fix this problem
If the problem is related to "quantity" of mods or sprites then the slowdown is inevitable. You'll need to manage it using the techniques mentioned above: fewer mods, lower quality, etc...
However, there's another possibility: one of your mods has malfunctioned and is constantly throwing errors. That one mod is therefore degrading the game's performance very significantly. In this case you should be able to achieve a drastic improvement by resolving the problem, or by removing that particular mod.
Please
try to play the game using the Flash Player Projector content debugger (available
here). Errors are normally hidden during gameplay, but this tool will allow you to see them. If an error occurs then it will immediately interrupt your gameplay and show a big obnoxious error message. That's okay, please take a screenshot (or copy-paste the error message) and post it here. We'll attempt to identify the problem and suggest a fix.
If you pursue this course then please continue to use the debugger tool until the problem has been fully investigated and resolved. We might manage to fix the first problem only to reveal several more underlying problems. Once we've dealt with
all of the problems (and hopefully improved your FPS performance), you can go back to using the normal Flash Player projector application.