Hey mocacinno, thanks for giving c-lightning a shot. The value mismatch is actually important, no one has ever tried to give that many funds to a lightning wallet so far, and indeed you stumbled over a bug when reading back the funds from the DB. It is fixed in a PR and should be merged soon, at which point the true value of the output will show up :-)
As for the disconnection I don't really know. Are you trying to connect to yourself? `connect 9735` seems to suggest that.
Hi,
It's great to see the dev team active on bitcointalk

I'll try to pull the new code, recompile and put the old ~/.lightning folder back to verify if i see the 50 tbtc value.
As for your second question, yes, i started lightningd on the same machine as bitcoind. Bitcoind is running in daemon mode, lightningd runs in a screen session. I then tryd to connect using lightning-cli on the same machine as lightningd and bitcoind were running. I verified using "lsof -i :9735" and found a possible error:
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
lightning 8622 testnet 4u IPv6 2484389 0t0 TCP *:9735 (LISTEN)
For some reason it's IPv6 instead of IPv4, eventough no other service is listening on this port... I tried many other ports, but the debug always shows
lightning_gossipd(9238): TRACE: Failed to bind on 2 socket: Address already in use
Afterwards it always seems to listen on the ipv6 socket...
EDIT:
on a sidenote, the bug is fixed

li/lightning-cli listfunds
{ "outputs" :
[
{ "txid" : "redacted", "output" : 0, "value" : 5000000000 },
{ "txid" : "redacted", "output" : 0, "value" : 1900000000 } ] }