S350 series configuration

Hello,

I could use some help setting up a new switch I purchased recently.  Honestly, I know enough to be danereous when it networking configuration so this is probaly pretty basic.  My apologies in advance...

The big picture is that I'm trying to set up an NDI network for our church - so I want a separate, dedicated wired LAN for this. This switch (GS324TP) seemed to fit the bill.  I like the PoE aspect as the NDI to HDMI converters I want to use can run on PoE.  Our chuch has an existing wired ethernet network - 10.10.100.0/24.  I envisioned the NDI network at a seperate subnet that hangs off of this network and routes onto the existing network.  I chose 10.10.200.0/24 for the NDI network.  I don't really want/need a DHCP server for the NDI network and plan to configure all the devices on this nework (just 2 computers and a one of the above converters for now) as static IP addresses.  I specificed the IP configuration of the switch:

• In System - Management - IP Configuration
• Set IP address of switch to 10.10.200.1
• Set Subnet mask to 255.255.255.0
• Tried to set default Gateway to 10.10.100.1 (the IP of the switch for the main church network) but this complained and wouldn't let me specify at IP not on the 10.10.200.0/24 subnet.  I think I specified 10.10.200.254.  What should this be?   

I then cabled the two computers and and the NDI convert into the first 3 ports of the switch.  I also cabled the 4th port back to main church network switch (10.10.100.0/24).  

My first problem/surprise was when tried to configure the first computer - an iMac.  The ethernet device defaults to DHCP and before I could change this, the computer could apparently "see" the DHCP server on the 10.10.100.0 subnet and successfully got an address (in the 10.10.100.0/24 range, of course).  I took this as sort of a good sign since the connectivity from my NDI nework back to the "core" switch was apparently there and working.  But this was not what I wanted so I manually configured a static address (10.10.200.10) for that computer (subnet mask 255.255.255.0) on the NDI network. 

Likewise, I configured the 2nd computer (a MacBookPro) as 10.10.200.11.  I configured the NDI converter as 10.10.200.12.  From the iMac I can now ping the MBP and the converter.  From the MPB I can ping the iMac and the converter.  I can also ssh between the two computers.  That's all good.  However...

Routing onto the main network (and out to the internet) is not working.  On either of the computers, trying google or any other general web address in a broswer is not working.  What I thought I'd have to do is set a default route on the NDI switch (10.10.200.0/24) to route back onto the "core" switch (10.10.100.x) by doing something like this. But this GS324TP switch doesn't seem to have a routing tab.  I'm guessing this has something to do with the (lack of) capabilites of the particular switch I bought (L2, L3, etc.)?

The other issue I'm having is with the NDI converter. The iMac (10.10.200.10) is running OBS and is set up to export its main output over NDI.  This should be working properly as the MBP computer (10.10.200.11) is running ProPresenter and can "see" the OBS NDI source and view it in ProPresenter.  However, the NDI converter (10.10.200.12) can not see the OBS source.  I have contacted the maker of the converter and this should work just fine.  

So clearly I don't have something configured properly.  Any ideas on what that might be would be appreciated.  

Thanks,

Darby