Change set RB800+RB250GS by RB1200

Hello
I want to change the set rb800 + rb250gs by a rb1200.

I would use the chip of switch of the rb1200.
For the test I did had trouble setting a “software vlan” on the switch ports to put him ips. The RB1200 crashed when I began to ping to an IP on the network of the same vlan.

Does anyone have experience with this kind of change?

The problem is understanding how to put an ip on a vlan placed on a port of participant of a switch (chip) work properly as in a bridge without using the chip switch