Strategy:

Start MS Publisher
Create Empty Document
File/Save, foo.pub
File/Exit.
copy foo.pub foo1.pub
Start MS Publisher
Create Empty Document
File/Save, foo.pub (one difference: Confirm overwrite)
File/Exit.

Compare foo.pub, foo1.pub.

These files should be identical.

Diff: Only 49 bytes.

The diffs in 1,5,6 - of 7, as usual.

This seems to be a "stub" of the main diff:
1132	2154	 0	 0	 	224	e0	 
1133	2155	91	5b	'['	211	d3	 
1134	2156	16	10	 	3	3	 
1135	2157	74	4a	'J'	88	58	'X'
1136	2160	239	ef	 	239	ef	 
1137	2161	170	aa	 	170	aa	 
1138	2162	199	c7	 	199	c7	 
1139	2163	1	1	 	1	1	 
... But it ends with a five. The others end with zero.......
1140	2164	5	5	 	5	5	 

This is the generic diff: 4 differ, 4 match, 4 differ, 4 match.
1252	2344	 0	 0	 	224	e0	 
1253	2345	234	ea	 	211	d3	 
1254	2346	13	d	 	3	3	 
1255	2347	74	4a	'J'	88	58	'X'
1256	2350	239	ef	 	239	ef	 
1257	2351	170	aa	 	170	aa	 
1258	2352	199	c7	 	199	c7	 
1259	2353	1	1	 	1	1	 
1260	2354	0	0	 	224	e0	 
1261	2355	91	5b	'['	211	d3	 
1262	2356	16	10	 	3	3	 
1263	2357	74	4a	'J'	88	58	'X'
1264	2360	239	ef	 	239	ef	 
1265	2361	170	aa	 	170	aa	 
1266	2362	199	c7	 	199	c7	 
1267	2363	1	1	 	1	1	 
1268	2364	 0	 0	 	 0	 0	 

Okay; this is a block of:
  00,ea,0d,4a,ef,aa,c7,01
  00,5b,10,4a,ef,aa,c7,01
vs
  e0,d3,03,58,ef,aa,c7,01
  e0,d3,03,58,ef,aa,c7,01
Two strings of 8 bytes, each ending in "01".

Or, another way:
  00,ea,0d,4a,ef,aa,c7,01	
  e0,d3,03,58,ef,aa,c7,01
and then
  00,5b,10,4a,ef,aa,c7,01
  e0,d3,03,58,ef,aa,c7,01

So, byte 1 is 00/e0; byte 5-8 is ef,aa,c7,01.
The diff is :
 00 ea 0d 4a ... vs :
 e0 d3 03 58

1380 (1252 + 128) : Again
1508 (1380 + 128): Again
1636 (1508 + 128): Again

.... outfile5 :
48804	137244	 49	31	'1'	 52	34	'4'
This is the "LOCALS@1\Temp\pub4.tmp" vs "LOCALS~1\Temp\pub1.tmp"

---- outfile6:

58468: Again

These 4 match the c6/c7 we've seen as part of the previous block:
60298	165612	182	b6	 	183	b7	 
+30
60328	165650	182	b6	 	183	b7	 
+440
60768	166540	182	b6	 	183	b7	 
+82
60850	166662	182	b6	 	183	b7	 

<pre>
$ bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 
ibase=16
E0D30358EFAAC7
63282406113651399
steve@elvis:~/c/pub/5$ date +%s
1181433392
</pre>
I can't see any correlation with the number 30D30358EFAAC7 and the current date, then. At least, not in UNIX terms.