Rotated the LNB.
Managed to get into the SRT settings, and am adding 68.5E.
Which frequency should I allocate to it, from this menu ?
I tested a couple, and nothing from the blind scan.
Check the label on the LNBF or the box it came in for the L.O. value, it will probably be 5150 or 5.150 depending if it is in MHz or GHz. Use that to select the option in the LNB Frequency for the Strong receiver.
If there is no L.O. value available from the LNBF label or box use a value of 5150 for the receiver. It is not a critical setting, all that will happen if you use an incorrect C-Band L.O. value will be that any frequencies scanned in will not be reported correctly, they will have incorrect frequency values but they will still give pictures.
The LNBF looks to be correctly orientatied for polarity skew. If a blind scan of the full C-Band frequency range does not lock any frequencies you may need to marginally rotate the entire mount/dish assembly on top of the pole by a small amount and repeat the blind scan. You might need to do this a few times to locate the satellite.
The frequencies you are looking for will be in the range of 3400 MHz to 4200 MHz, if you are using the Strong SRT default transponders you need to use ones that are in this frequency range. One of your pictures (srt 4.jpg) shows you are using Ku-Band transponder (10989V) for scanning. If you have set the LNB Frequency in the receiver to 5150 it should automatically blind scan the range of 3400 to 4200 MHz.