[Lazarus] Noobie - Interface problem in Windows

[Martin]

Hi,

I am a bit of a noobie to Lazarus and I have been designing an app with 
Lazarus running under Linux. It all seemed to be going well. Tonight I 
booted into Windows and decided to quickly compile the app to see what 
it looked like and there is a problem with a blue background that I 
don't get compiling under Linux.

See these screenshots as an example:

Running under Windows 7, Lazarus 1.0.12 fpc 2.6.2
https://dl.dropboxusercontent.com/u/3940444/laz_windows%201.0.12%20fpc%202.6.2.png

Running under Linux (LMDE), Lazarus 1.0.10 fpc 2.6.2 gtk
https://dl.dropboxusercontent.com/u/3940444/laz_linux%201.0.10%20fpc%202.6.2.png

Running under Linux (LMDE), Lazarus 1.3 svn fpc 2.6.2 Qt
https://dl.dropboxusercontent.com/u/3940444/laz_linux%201.3%20fpc%202.6.2.png

The tabs are a TTabControl rather than a TPageControl. My thinking 
behind using a TabControl was that only minor UI changes will be 
required when the tab changes and I could do this with code. If I used a 
PageControl I would have had to make copies of all the UI items for each 
page, which would mean a lot of time, effort and probably a bigger binary.

Not sure why I am getting a blue background only in Windows, when it 
looks fine in Linux? All the UI elements below the TabControl appear to 
be it's children in the object inspector. Should I have placed a panel 
before placing the other UI elements?

I very much appreciate any help or guidance you can offer me.

Thanks & best regards,

Martin