kinstalltheme: 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 CentOS possible default full paths are:

/usr/bin/kinstalltheme - from package: kdelibs3

You may install the required package with command yum install {package}

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