Error converting

[The-Gmann]

After trying to convert this mod (which i love), https://www.curseforge.com/minecraft/mc-mods/the-fletching-table-mod i got this error:

[22:26:12] [main/INFO] (PatchworkUI) Welcome to Patchwork Patcher!
[22:26:12] [main/INFO] (PatchworkUI) Patchwork is still an early project, things might not work as expected! Let us know the issues on GitHub!
[22:28:13] [pool-2-thread-1/WARN] (Patchwork) Merged minecraft jar not found, generating one!
[22:28:13] [pool-2-thread-1/INFO] (ResourceDownloader) Downloading Minecraft jars
[22:28:32] [pool-2-thread-1/INFO] (ResourceDownloader) Merging and remapping Minecraft jars
[22:28:53] [pool-2-thread-1/ERROR] (Patchwork) Couldn't setup Patchwork!
java.lang.ArrayIndexOutOfBoundsException: 1
at net.patchworkmc.patcher.mapping.Tsrg.readMappings(Tsrg.java:43) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.util.ResourceDownloader.setupAndLoadMappings(ResourceDownloader.java:99) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.util.ResourceDownloader.createAndRemapMinecraftJar(ResourceDownloader.java:75) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.Patchwork.createInner(Patchwork.java:414) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.Patchwork.create(Patchwork.java:372) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.ui.PatchworkUI.startPatching(PatchworkUI.java:300) ~[patchwork-patcher-0.4-ui.jar:0.4]
at net.patchworkmc.patcher.ui.PatchworkUI.lambda$main$9(PatchworkUI.java:265) ~[patchwork-patcher-0.4-ui.jar:0.4]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_291]
at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_291]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) [?:1.8.0_291]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) [?:1.8.0_291]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [?:1.8.0_291]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [?:1.8.0_291]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_291]