If you're using the 20_ON_D20 code/icon in English or any double-digit results code/icon in any other language, then download Dicier v1.3.1 to fix it (make sure to follow the de-/re-installation instructions at the start of Chapter 2 of the User Guide).

If you're not using these codes/icons, then stick with the current v1.3. The bug fix will be included in v1.4 onwards, so there's not much point spending time updating your copy of Dicier just to fix icons you're not using.