skeinforge-craft: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/skeinforge-craft - from package: skeinforge

You may install the required package with command yum install {package}
Error in other languages:
skeinforge-craft: bevel nie gevind nie
skeinforge-craft: comandă negăsită
skeinforge-craft: comando não encontrado
skeinforge-craft: commande introuvable
skeinforge-craft: command not found
skeinforge-craft: käsku ei ole
skeinforge-craft: không tìm thấy lệnh
skeinforge-craft: komanda nerasta
skeinforge-craft: Kommando nicht gefunden.
skeinforge-craft: kommandot finns inte
skeinforge-craft: komut yok
skeinforge-craft: nie znaleziono polecenia
skeinforge-craft: níor aimsíodh an t-ordú
skeinforge-craft: no se encontró la orden
skeinforge-craft: no s'ha trobat l'ordre
skeinforge-craft: opdracht niet gevonden
skeinforge-craft: parancs nem található
skeinforge-craft: perintah tidak ditemukan
skeinforge-craft: príkaz nenájdený
skeinforge-craft: příkaz nenalezen
skeinforge-craft: команда не найдена
skeinforge-craft: командата не е открита
skeinforge-craft: 命令找不到
skeinforge-craft: コマンドが見つかりません