Thanks for all your feedback. It's very useful for me. I hope the Beta 6 fixes the issues you reported.
At floor level, several models still show a square opening at top. But, as soon as I give the model a slight elevation, the gaps are closed.
That bug is fixed. The empty space around round doors and windows are filled correctly as soon as they are used (the first time and when a sh3d file is reopened).okh, first I'm glad your copy / paste / undo / redo issues were fixed with a Java upgrade. Always good to know if an other user encounters the same issue.
Second, do not worry about reporting issues here. If I publish Beta versions, it's to show new features, but also to let you test them and report bugs and bad/missing ideas I could have.
About transparency issues, I think it's due to the graphics card. I noticed this kind of bug myself many times, and I'm not sure it can be fixed. So, don't abuse of transparency, whether it comes from window panes or transparent textures.
it is interesting to see how 4.2+ will deal with legacy files
Legacy sh3d files will be maintained. It's the only warranty I chose to give for this feature. So, adding the same round door in Sweet Home 3D 4.1 and Sweet Home 3D 4.2 will give different results, unless you set the correct cut out shape in its sh3f file. But opening with Sweet Home 3D 4.2 a sh3d file designed with Sweet Home 3D 4.1 will render the same as it was designed at first. So no surprise for users who will upgrade. 
I don't understand why it is slashed diagonally across the arch.
This bug should be fixed in the Beta 6.By the way, if you really feel bad about SVG path handling, you can also play with transparent parts of a door or window because they are taken into account in the automatic cutout shape detection. Thus, okh, if you add a transparent box at the bottom of your North arch, it will give a correct result.
The Beta 6 improves also the management of non-maximized and maximized sizes of windows when a sh3d file is reopened. This should fix some issues that were visible mostly under Mac OS X.
It improves also the management of hidden panes when you resize the main window. For example, if you move a divider to hide the 3D view, the 3D view won't reappear when you enlarge the window. This improvement fixes also a bug that made an empty zone appear under the plan after a window enlargement, when the 3D view is displayed in a separate window.
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Emmanuel Puybaret, Sweet Home 3D creator
