Forum bug. I can't download your .blend file because the names of the other files are overlapping it.
@Shadow_Master, There's no need to make your sign multiple objects that require multiple materials. I would also recommend adding any text to the models texture, rather than modeling individual letters.
Here's an attachment with an updated .obj file for you with the sign mapped to a single texture and a video showing how I did it. I'm using an older version of Blender, but it should load up fine for you:
Here hotkeys I used for the video:
-Shift+Right-click to select multiple object then Ctrl+J to join them into a single mesh.
-Tab for edit mode
-A to select all or B+Left Click to drag and select
-Right-click to select a vert, face, etc. then Ctrl +L to select the entire mesh it is a part of
-U to bring up the unwrapping option, and 1,3 and 7 keys on the number pad to change perspective then "project from bounds" to unwrap --the selected faces the way they appear in the viewport.
S to scale, or S+ x,y or z to scale on that specific axis.
Don't give up on Blender. You're not going to find a better option and it's worth the extra time to learn. Very fast and efficient modeling program once you pick up on the hotkeys.
EDIT: Forgot attachments.
Here you go: