Minecraft crashes-Mcedit filters caused this

Hi. I have been using mcedit on my cool "Redstone house" world. I used "/give [my name] [id of diamond sword] 64" to get 2 stacks of diamond swords. I placed them in a chest. I used Sethbling's 'Add Attributes' and 'Modify item strings' filters on the items.

When i logged back into minecraft and opened up the chest,when i went to grab a sword Minecraft froze and closed. My launcher came up with this crash report:

---- Minecraft Crash Report ----
// There are four lights!

Time: 03/07/13 17:21
Description: Ticking player

java.lang.IllegalArgumentException: Modifier name cannot be empty
	at org.apache.commons.lang3.Validate.notEmpty(Validate.java:398)
	at oq.<init>(SourceFile:31)
	at tm.a(SourceFile:94)
	at xz.D(SourceFile:580)
	at oc.l_(SourceFile:1159)
	at ua.l_(SourceFile:203)
	at js.h(SourceFile:180)
	at jx.a(SourceFile:205)
	at et.a(SourceFile:136)
	at cm.b(SourceFile:64)
	at jx.d(SourceFile:59)
	at ka.b(SourceFile:37)
	at bkr.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bko.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hf.run(SourceFile:582)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at org.apache.commons.lang3.Validate.notEmpty(Validate.java:398)
	at oq.<init>(SourceFile:31)
	at tm.a(SourceFile:94)
	at xz.D(SourceFile:580)
	at oc.l_(SourceFile:1159)
	at ua.l_(SourceFile:203)

-- Player being ticked --
Details:
	Entity Type: null (js)
	Entity ID: 183
	Entity Name: cjfulcher
	Entity's Exact location: 16.25, 237.00, 6.35
	Entity's Block location: World: (16,237,6), Chunk: (at 0,14,6 in 1,0; contains blocks 16,0,0 to 31,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Entity's Momentum: 0.00, -0.08, 0.00
Stacktrace:
	at js.h(SourceFile:180)
	at jx.a(SourceFile:205)
	at et.a(SourceFile:136)
	at cm.b(SourceFile:64)
	at jx.d(SourceFile:59)

-- Ticking connection --
Details:
	Connection: jx@13cb35da
Stacktrace:
	at ka.b(SourceFile:37)
	at bkr.b(SourceFile:84)
	at net.minecraft.server.MinecraftServer.t(SourceFile:488)
	at net.minecraft.server.MinecraftServer.s(SourceFile:405)
	at bko.s(SourceFile:124)
	at net.minecraft.server.MinecraftServer.run(SourceFile:339)
	at hf.run(SourceFile:582)

-- System Details --
Details:
	Minecraft Version: 1.6.1
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.7.0_17, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 146826024 bytes (140 MB) / 316276736 bytes (301 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 1 total; -Xmx1G
	AABB Pool Size: 278 (15568 bytes; 0 MB) allocated, 267 (14952 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 51 (2856 bytes; 0 MB) allocated, 38 (2128 bytes; 0 MB) used
	Player Count: 1 / 8; [js['cjfulcher'/183, l='Cjfulcher's Redstone House', x=16.25, y=237.00, z=6.35]]
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.

I have unmodded Minecraft, as you can see from the end of the crash report. So yeah,you can call me stupid,whatever. But i have another problem. I accidentally broke the chest,which caused the chest to splutter out the 'infected' diamond swords. It put them into my hotbar,which instantly crashed my Minecraft.

So,basically, i CANNOT even go into my world. I've spent weeks working on the project without backing it up. If you can help me,it'd be great,but i have doubts.