Errors with ascii conversion?

[ceruleanReverie]

Hi, I'm trying to make a simple function to convert text to rot13. I'm using skutilities' ascii expressions to accomplish this, however I get errors in console whenever I try to convert from ascii back to text.

Skript Version (do not put latest): Skript 2.2 (dev35b)
Skript Author: Bensku
Minecraft Version: 1.12.2
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Full Code:

function rot13(input: text) :: text:
    set {_output} to ""
    set {_string::*} to {_input} split at ""
   
    set {_size} to size of {_string::*}
    delete {_string::%{_size}%}
   
    loop {_string::*}:
        set {_ascii} to convert text "%loop-value%" to ascii
        set {_ascii} to {_ascii} parsed as an integer
        if {_ascii} is between 65 and 90:
            set {_caps} to true
        else if {_ascii} is between 97 and 122:
            set {_caps} to false
        else:
            set {_output} to "%{_output}%%loop-value%"
       
        if {_caps} is set:
            set {_new} to {_ascii} + 13
            if {_caps} is true:
                if {_new} > 90:
                    set {_new} to {_new} - 26
            else:
                if {_new} > 122:
                    set {_new} to {_new} - 26
           
            set {_new} to {_new} parsed as an integer
            set {_replace} to convert ascii {_new} to string
            set {_output} to "%{_output}%%{_replace}%"
       
        delete {_caps}
   
    return {_output}

Console Errors:

pastebin

Addons:
SkUtilities (0.9.2), skquery, skrayfall, advancementsaddon, facsk, mundosk, tuske, vixio, wolvsk (the others really shouldn't be relevant)

Have you tried searching the docs? Yes
Have you tried searching the forums? Yes

---

The function gets called by a simple command, like so:

command /rot13 <text>:
    description: Returns a rot13 cipher of any text you provide.
    executable by: players and console
    trigger:
        set {_result} to rot13(arguments)
        message "&3Result: <tooltip:§dClick to copy text.><suggest command:%{_result}%>&f%{_result}%"