In 4.4.3 there are still some UV generating tools to help out. There are two in 4.4.3 and prior though.
Open the mesh in the mesh viewer/editor > Menu Bar > Windows > Generate UVs > a tab will open in the bottom right under the details panel >
You will have two options here:
Create New UV and you can select the channel - This will pelt map and break apart chunks of your mesh to get a UV. I wouldn’t recommend this method as it’s rarely produced good results with more complex or even simple objects at times.
The second option is to base the UV creation off the UV0 for the texture. This is the current (more refined) method that is in 4.5 and later. This will look at the UVs that are split in UV0 and repack them into UV1 for the lightmap.
Option two is the more preferred method. However, if you want the most control over your UVs it is recommended to use an external program and make a custom LM.
Thanks!