Topic: memory usage

hi,  not sure if the list is still active as I haven't posted here in a while, but I've been working on a project  for a while now and I have a question about memory useage. so as a really quick overview the idea of the project was to create a set of tools which would allow the user to be able to create/make their own audio game but without any scripting being needed by the end user. the projects coming along nicely, its fairly large in size now  probably around 17000 lines of code or so, but I've started to think more and more about memory usage so its running as efficiently  as possible. so my question is regarding global code, so I've been looking at everything that i'm using as globals, and there's a lot of stuff there, specifically most of the tools used to create a game are menu driven and I created my own menu class, now a lot of these menus since they are used over and over are created as global objects,  so i'm wondering from a system perspective since I've now got so many of these menus as global objects whether this is likely to hold up a big space of memory and potentially as the project gets bigger slow it down, the alternative is I could create the menus as and when they are needed  which although might cause a small delay  generating wouldn't then be held in memory since they would be destroyed  once used. so I guess really my question is from a coding/scripting standpoint how detrimental to memory useage is having tons of global objects and varibles? hope this makes sense as i'm still no expert when it comes to BGT and I couldn't find  a lot about memory useage within the BGT help documentation.