It seams, you did not understand how flash loads movieclips.
Every single movieclip needs its own level - if you reuse a level, the movieclip residing there will be overwritten.
After you are using Flash 8 and AS2.0, and the next stept to AS3 has to be gone one day, dont get used to use fixed levels.
Get used to objects, containers etc. to manage your movieclips.
Even though Flash 8, AS2 still allows you using levels (if you dont use components

), Flash CS3/4 ... AS3 do not support this inflexibla static addressing anymore.
At first, it takes a little more learning - but then it makes life, at least with larger sites, much easyer and managable.