Hmmm... Here is what I did - followed the example at your site:
1. netinstall started.
2. Net Booting -> Boot Server enabled / IP in Local LAN assigned (10.0.4.13)
3. Set router to boot ...
3. Select router through MAC in netinstall
4. Select Software Package -> RouterOS for routerBoard RB5xx & RB1xx
and click install
5. Waiting - 5secs later - I have a ready again in netinstall for the MAC Address showing up again.
Router Serial terminal side:
Select boot device:
* e - boot over Ethernet
n - boot from NAND, if fail then Ethernet
c - boot from CompactFlash only
1 - boot Ethernet once, then NAND
2 - boot Ethernet once, then CompactFlash
o - boot from NAND only
b - boot chosen device
your choice: b - boot chosen device
trying bootp protocol... OK
Got IP address: 10.0.4.13
resolved mac address 00:16:CB:A6:89:EB
*transfer started ..................... transfer ok, time=3.02s
setting up elf image... OK
jumping to kernel code
Welcome to MikroTik Router Software remote installation
Press Ctrl-Alt-Delete to abort
software-id: 7X0F-3TT key:
Waiting for installation server...
Note - that when I do all that through my own tftp/dhcp-servers, it workswithout an issue.
Of course - I have deactivated the local bootp/tftp/dhcp servers before using netinstall.
I even booted into windows to make sure nothing there is giving me any issues.
Even removed the Windows Firewall etc.
Any hints ?
BTW: A ctrl-alt-delet in the serial terminal does not work