Loading HDRI Problem

I have the Dimension Theory HDRIs Yosemite. They are really gooid, but why so difficult to load?
The only way i can get them to load properly;-
1. Go to Content Library and right click DT-Yosemite XX
2. Go to Scene Tab and Delete Yosemite XX
3. Go to Render Tab, click the environment map and load YosemiteHDRXX.tif
Why is this necessary?
Am I doing something wrong?
Comments
They are made for 3Delight, loading the DT-Yosemite XX would be all that was required there. However, for iray the uber Environment light isn't auto-converted (sounds like an opening for a script) so you have to manually assign the map to the Ennvrionment in Render Settings.
So I am getting it right?
The easiest way is to double click to load, go to Environment and click on Environment Map to load a texture and choose the dt-yosemitehdr.tif. Go to scene and delete the Yosemite items. The hdr will now show up in the dome under Iray. Don't use the dt-yosemiteenv.tif as that is just lighting. You could also use the .jpg if you want too.
Thanks both!