When using list elements, breaks are inserted between lists...
for example, using:
[ list]
[*] first item
[*] second item
[*] third item
[ /list]

parses as...
[ list]<br>
[*] first item<br>
[*] second item<br>
[*] third item<br>
[ /list]

<ul><br><li> first item</li><br><li> second item</li><br><li> third item</li></ul><br>

This causes the display to appear as:

[list]

[*] first item

[/*:m][*] second item

[*] Third item

[/*:m][/list:u]

See This post for an example.

Hopefully this worked... no preview.