Can't Open Indexing_macos.dmg on OS X El Capitan 10.11.5

Excited to participate in the Indexing event on July 15-17, but I can't even get past opening up the disc image of the indexing app I was asked to download. After downloading and double clicking to open, I get the following error message after waiting 1-2 minutes... "The following disk images couldn't be opened. Image: Indexing_macos.dmg; Reason: Operation timed out"

I don't recall ever having any other rouble opening a disc image before.

Any hints on what needs to happen to open the image and install the app?

It's possible the dmg didn't download correctly – you could try deleting it and downloading again after checking your internet connection, and maybe using a different browser. I'm currently getting an Internal Server Error when I try to download the indexing program at FamilySearch.org, so I'm not able to test on my OS X 10.11.5 computer, but I'll try to remember to test later. Or, maybe the Internal Server Error is an indication of problems that need to be fixed on FamilySearch's end.

Figured out the issue. I saw the note above the Download button stating "If you are new to indexing, you will need to install Java SE6 first." and figured I was good since I had the latest version of JAVA installed. When things weren't working as noted above, I used the link to install Java SE6, dowloaded it, installed it, restated my computer, and the Indexing_macos.dmg I had downloaded previously opened (albeit very slowly). Similarly, the install process ran quite slowly as well, but did finish successfully and I was able to launch the Indexing app after it it finished installing.

Great!