I started this discussion at http://www.shape5.com/component/option,com_smf/Itemid,75/topic,35397.new/
but moved it here because I subsequently renewed my subscription to Shape5, upgraded my sandbox site to J3.x, and then installed the Oasis template.
When I have one of the two packaged templates set as the site's default, I can see the site. When I change to Oasis for the default, I can't see the site. The same thing was happening when I had Joomla 2.5 and installed the free Vertex template (see above discussion link).
I get a blank browser page when I have the default set to Oasis and click on preview. But, if I have the default template set on one of the packaged templates, the Oasis preview works. See http://migration.tnhillbillie.net/index.php?tp=1&template=oasis
My domain is running PHP5.4 on the server. I haven't made any other changes to the default installation except to add Akeeba, the S5 Flex Menu plugin (in anticipation of using Oasis), and JUpgradePro.
I'm anxious to get started on customization, so I look forward to suggestions.