CE 4.0 VM: Content tab stops working depending on client location?

After fighting with the CE 5.0 VM image, which I can get to boot but can't get to run Kaltura worth a damn for varying reasons, I reverted to the CE 4.0 VM image which I did have working at one time. I went through the CE 4 VM image setup 15min video, so the admin console works and the management console works. But the Content tab on the management console just gives me a blank panel.

Here's the weird part: It seems to depend on the network location whether the Content tab works or not. A Windows 7 PC with IE9 and Flash 11.5 will not work if it's in the same IP subnet, but it will work if it's on a different subnet.

The VM in question is running on an ESXi host that uses VLANs and a VLAN-capable switch, so I can give a VM a public IP address while not compromising the connectivity of other VMs. One of the test clients is on a private VLAN and there's a NAT-capable router for that. DNS is working; I run my own DNS, and I can resolve hostnames correctly.

Hm, maybe I don't need to do the /etc/hosts hack if DNS is working properly?
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