You should specify format for signature

[ChristopherA]

I tried entering the bare signature for my sentiment, and I get the error:

Sorry, this signature looks wrong. Try again?

Address: 1F6D7hP1JptubR1WEjuFH8a6CPSCSi7m2H
Support: sentiment:support:3459832595df691ad738e33164c3620f3f9d77625471f65a77ac8a1b450f0940

Inputs.IO Signature: HKqxmraX50uo5EUGWNRRD1IT4pv6yVwCo9e0EufOU7roiL1UvDLjuywli/04g7jVBYYd/9bxIXVHnbajksB+rTc=

I tried a couple of other formats, and ultimately found that the Multibit signature was required:

HLQAM44ruY/RxZtx4p4fwSRsc9d7aP3n9m2T8GWAPLm8P/+G+hVis7UNKgPYC3IdvYcg7Npdz9jO6LEyQlxBMX0=

But it could have been armory:

HBAy3g95wD5XMEtx6tj1Eo1JXpaBxm55F9PzCPqrcMiVWwQ4QpqRH6cJw5788d8C
IyXNptu1TWRuYIN58h3hnHFzZW50aW1lbnQ6c3VwcG9ydDozNDU5ODMyNTk1ZGY2
OTFhZDczOGUzMzE2NGMzNjIwZjNmOWQ3NzYyNTQ3MWY2NWE3N2FjOGExYjQ1MGYw
OTQw
=0EWa

Or armory clearsign:

G7NNRqnYo5rFZj8VscstE6KcorrQpqktSD09AuH/4/Q5rVttd8iPAs4QbJz2YIJr
aGTgJz40vx5bwQ/Grsy2n/k=
=jmK3

Or even armory hex:

9e877bb7d44306920221487abe40cf697264edca3227429f045de29e2450306e09ffeaf57af749f3b9914b8be072a861c6caad283aa2fa079a44a50777b63ff7

You should specify which format(s) you support, and ideally also point someone to a signing tool. I used the old brainwallet.js software, but that is no longer available.