When picking file type in the save as dialog, use any of the "rectangular export" ones, they will prompt you to define the rectangle of the export after hitting save.

Have you considered using a different style of roads? Those dashed lines works on overland maps because they're only representative of the feature, but on close-up maps like these, they come out looking a bit out of place. Maybe a dirt brown fill with a small edge fade instead?

Most scale bars are 100, but there are exceptions like the style from that thread, where it is 200. Some styles also have multiple lengths, like the Schley overland style which as two at 100 and one at 200

The easiest way to check the scale of it in any style is simply to place it (Make sure the current symbol scale is 1) and measure it using the Info->Distance tool.

Digging a bit, I found that transparency only works for images if they are set to use alpha transparency in CC3+.

Use the :CC2EDIT: on the image, and switch it to alpha transparency, and it should work fine. (remember to thaw that frozen layer first, otherwise you can't edit it)

That problem occur if you just insert the house image into your drawing instead of the actual house symbol.

There are more information in the symbol than just the image, and CC3+ needs this information to generate a proper floorplan from the building.

The reason you have just a house image and not a house symbol in your map in the first place is most likely through the use of the :ICON_CATALOG: button. When you click this, you can either browse and pick a symbol catalog file (.fsc file), OR you can browse to a folder full of images, pick any image, and then have all the images from the folder showing up in the symbol catalog window. But if you do the latter (pick an image instead of symbol catalog when browsing) it means you will only get them as images, NOT symbols, because the extra information is in the symbol catalog file.

Instead, you should ALWAYS pick a symbol catalog file (.fsc), or just use the symbol catalog buttons in the toolbar as they will load the symbol catalogs properly.