I'm struggling to get DHCP Server Option 43 working with a Genexis router.

To get the router to talk to our CWMP server, I can manually enter the URL details on the Genexis unit
http://10.10.25.6:7547

But to do this automatically, whatever I set up in the Mikrotik DHCP server, the Genexis does not seem to be interested - even if I strip it back to the simple IP address, HEX encoded.

Here is what I have set up at the moment:
/ip dhcp-server option
add code=43 name=acs value=0x01040a0a1906
/ip dhcp-server network
add address=10.10.90.0/24 dhcp-option=acs dns-server=\
208.67.222.222,208.67.220.220 gateway=10.10.90.1 netmask=24

Which is being picked up by the Genexis router as it reports:
Option 43 : vendor-info 01040A0A1906

But the CWMP server URL is empty.

I've tried
0x0a0a1906 (Option 43 : vendor-info 0A0A1906)
'10.10.25.6' (Option 43 : vendor-info 0A0A1906)
s'10.10.25.6' (Option 43 : vendor-info 31302E31302E32352E36)
s'http://10.10.25.5' (Option 43 : vendor-info 687474703A2F2F31302E31302E32352E36)
s'http://10.10.25.6:7547' ( Option 43 : vendor-info 687474703A2F2F31302E31302E32352E363A37353437)

None of which appear to be picked up by the Genexis router.

Any clues?
Anything I can turn on in the logging to see what interactions are taking place?

In the Genexis manuals they provide details for setting up Option 43 on a Microsoft DHCP server:

[u]Step 1: Declare option space.[/u]
These lines must be placed in the global scope.
option space bbf;
选择bbf。acs code 1 = text;
选择bbf。provisioningcode code 2 = text;
选择bbf。minwaitinterval鳕鱼e 3 = unsigned integer 32;
选择bbf。retryintervalmultiplier code 4 = unsigned integer 32;

Step 2: Provide values for each component.
While it is possible to add these lines as global parameters, it is strongly advised they be put in subnet, pool or group scope.
vendor-option-space bbf;
选择bbf。acs “http://192.168.42.239:8080/acs”;
选择bbf。provisioningcode “provisioning code value”;
选择bbf。minwaitinterval 500;
选择bbf。retryintervalmultiplier 4000

Where Option 43 (Vendor Specific Information)
This option is used to provide the CPE with information about the location of the ACS used for managing the CPE via CWMP.
This information has four components. The follow table lists these components, their data type and whether or not they must be provided.
Code / Name /Description / Required
1 / ACS / The URL of the ACS / YES
2 / Provisioning Code / An operator defined string used by the ACS server to group CPEs. / no
3 / Minimum Wait Interval / CWMP session retry minimum wait interval /no
4 / Retry Interval Multiplier / The initial value of the CWMP session retry interval multiplier / no

Table 22. Broadband Forum Option 43 codes
(https://www.broadband-forum.org/technical/download/TR-069_
Amendment-5.pdf)

OK - sorted now. Just need to take more time reading the manual.
The full URL needs to be converted to hex so
http://10.10.25.6:7457becomes
68 74 74 70 3a 2f 2f 31 30 2e 31 30 2e 32 35 2e 36 3a 37 35 34 37

That's 22 bytes and for Option 43 it's Code 1, so I needed to add the hex for "1" (01) and "22" (16) in front of the string and add 0x to say it's in HEX and now we're working fine.
Full code is

0x0116687474703a2f2f31302e31302e32352e363a37353437

/ip dhcp-server option
add code=43 name=acs value=0x0116687474703a2f2f31302e31302e32352e363a37353437

sorry for resurrecting the dead, can you share how to pass ACS username and Password?