The size of imported items can only be increased proportionally in all directions. ARCHLine.XP also provides a solution if you only want to resize it in one direction.
1, Select the imported object and enter its properties.
2, In the group of Cut and Stretch. Cutting plane at % set the direction and place of the cutting or stretching.
3, Switch off the Uniform 3D scaling operation function and change the height / depth / length of the object to the desired value. Click on the refresh icon to see the changes.
4, The program will stretch / cut the object in the place you set in the 2. step, without changing any other parameter.