fit_spline_xform: command not found

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 Debian possible default full paths are:

/usr/lib/cmtk/bin/fit_spline_xform - from package: cmtk

You may install the required package with command apt-get install {package}

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