Preloaders are the bane of all flash newbies and provide the first real test of Flash-hood. There are also many different ways of approaching the design too. Some use javascript, some only use two frames, some load every object behind a false background and others use tweened shapes and lots of keyframes. Well just to confuse you more, here is another way of building an advanced preloader but it's probably the best way too. This preloader uses the actual byte values for each frame of your movie loaded in via a text file. Below is the timeline. The length is inconsequential but in this example it's 86 frames.

To create this preloader we have to first create the text file which is done by modifying the contents of the Size Report. To do this you need to first generate a size report. Select File> Publish Settings and check the generate size report option (see below). Now publish your flash movie (File> Publish). You will now have a size report in the same directory as your .SWF file. Open it up and have a look at it.

In your size report you will have a list of frames, one through to x (x being total number of frames). To create your text file of variables it's just a matter of modifying the contents until you have something like this (see below) and saving it as "byte.dat"(don't forget the two important variables at the end, these should be self explanatory)

&1=2165&2=305&3=15&4=440&5=15&6=532&7=479&8=504&9=532&10=521&11=495&12=416&13
=496&14=533&15=556&16=569&17=566&18=555&19=526&20=491&21=418&22=399&23=527&24
=536&25=568&26=30&27=524&28=479&29=504&30=532&31=521&32=9&33=415&34=496&35
=533&36=556&37=565&38=562&39=555&40=526&41=9&42=418&43=9&44=527&45=536&46
=9&47=523&48=479&49=504&50=533&51=9&52=9&53=415&54=496&55=533&56=560&57=565&58
=562&59=555&60=526&61=9&62=417&63=9&64=527&65=537&66=9&67=523&68=479&69=504&70
=533&71=9&72=9&73=415&74=496&75=533&76=560&77=565&124=562&79=555&80=526&81
=9&82=417&83=9&84=527&85=537&86=9&frame_total=86&bytedata_loaded=1&