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before but always freezing at the « starting kernel … » phase.......
Probably it does not freeze, it is the normal behavior as the kernel will not output to the console in this case. What should happen is that after some time the telnet client should popup to connect to the nas. Does that happen? (Telnet client must be granted to pass your firewall if that is enabled).
If the standalone kernel runs then it can be used to assemble the raid and access your data but it is not easy. You could do the dame on a PC running linux if you connect the disk to that pc.
If the standalone kernel runs then also it should be able to do a normal boot. However apparently the lacie firmware is corrupt preventing booting. Installing lacie firmware is possible if you can get the required files. If you install our firmware all data on the nas will be lost as we use anther partition structure. But the standalone kernel could be used to try to safe your data if the raid array is ok.