Yes. Here is the output:
Switch1:
NIC 1: MAC: 080027A8E1D9, Attachment: Host-only Interface 'VirtualBox Host-Only Ethernet Adapter', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Bootpriority: 0, Promisc Policy: allow-all, Bandwidth group: none
NIC 2: MAC: 080027FFEB8C, Attachment: Internal Network 'link11', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 3: MAC: 080027128323, Attachment: Internal Network 'link12', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 4: MAC: 080027F9BBE3, Attachment: Internal Network 'link13', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
Switch2:
NIC 1: MAC: 0800279CB519, Attachment: Host-only Interface 'VirtualBox Host-Only Ethernet Adapter', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Bootpriority: 0, Promisc Policy: allow-all, Bandwidth group: none
NIC 2: MAC: 080027185BAE, Attachment: Internal Network 'link21', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 3: MAC: 080027BD9FAC, Attachment: Internal Network 'link22', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 4: MAC: 080027BC098A, Attachment: Internal Network 'link23', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
Router1:
NIC 1: MAC: 080027909C86, Attachment: Host-only Interface 'VirtualBox Host-Only Ethernet Adapter', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Bootpriority: 0, Promisc Policy: allow-all, Bandwidth group: none
NIC 2: MAC: 080027CBAD8B, Attachment: Internal Network 'link11', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 3: MAC: 080027F1B83E, Attachment: Internal Network 'link12', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
NIC 4: MAC: 080027A8CFF7, Attachment: Internal Network 'link21', Cable connected: on, Trace: off (file: none), Type: Am79C973, Reported speed: 0 Mbps, Boot priority: 0, Promisc Policy: allow
-all, Bandwidth group: none
I have changed the network topology, but it is basically the same settings, and the problem is the same even in this setup. I tried with Windows-host and with Switch that acts as a host. I can ping from one host to another's default gateway, but can't reach the host.