We are also on SnapCenter Server 4.1.1 (using non-ova/Windows based Plug-for Vmware), and this is the general guide, that we will be following to switch to OVA version 4.3.x.
Step 1:
Deploy OVA:
SnapCenter Plug-in for VMware vSphere 4.3:
https://library.netapp.com/ecm/ecm_download_file/ECMLP2863451
Step 2:
Migrate the existing meta-data,resource-groups/policy etc:
Migrating from SnapCenter Plug-in for VMware vSphere to virtual appliance (OVA):Page-80
https://library.netapp.com/ecm/ecm_download_file/ECMLP2863452
The migration command in the guide above, migrates metadata from SnapCenter 4.0, 4.1, and 4.1.1 only. As you are running 4.0, so you should be good.
Item Supported versions for 4.3:
vCenter vSphere Flex client: 6.0U3, 6.5U2/U3, 6.7x, 7.0
HTML5 client: 6.5U2d/U3, 6.7x, 7.0
Thanks!