Cheat:

 While playing, type RASPUTIN. The mouse pointer will turn into a
 haircross and you can now shoot lemmings by clicking on them.
 Lemmings killed in this way will count as saved.

 From Thomas Petersson, tpetersson@wineasy.se

Codes:

 FUN
 1   --------    2   BLIMBING    3   FANAGALD
 4   DRICKSIE    5   KURTOSIS    6   GREGATIM
 7   WALLAROO    8   AVENTAIL    9   GAZOGENE
 10  JINGBANG    11  DIALLAGE    12  BUNODONT
 13  NAINSOOK    14  YAKIMONA    15  FUMITORY
 16  CINGULUM    17  BESLAVER    18  ANABLEPS
 19  QUINCUNX    20  TARLATAN

 TRICKY
 21  KAMACITE    22  GUMMOSIS    23  PRODNOSE
 24  NGULTRUM    25  COTTABUS    26  BEDAGGLE
 27  EPICALYX    28  HOMALOID    29  LALLYGAG
 30  BILABIAL    31  CACOFOGO    32  METAVURT
 33  SLOWBURN    34  PELLUCID    35  MAKIMONO
 36  KHUSKHUS    37  DISPLODE    38  RACAHOUT
 39  ORGULOUS    40  DUNCEDOM

 TAXING
 41  CABOCEER    42  GEROPIGA    43  BONTEBOK
 44  EMPYREAL    45  LANGLAUF    46  NANNYGAI
 47  SARATOGA    48  QUINTAIN    49  MUSQUASH
 50  ZOMBORUK    51  SKILLING    52  WOBEGONE
 53  BINDIEYE    54  FRAXINUS    55  LINDWORM
 56  CURLICUE    57  HANEPOOR    58  IDEMQUOD
 59  BLANDISH    60  MALAGASY

 MAYHEM
 61  CHORIAMB    62  GARGANEY    63  KAOLIANG
 64  MAROCAIN    65  OBTEMPER    66  TASTEVIN
 67  VELLOZIA    68  BORACHIO    69  JACKAROO
 70  COOLAMON    71  BANAUSIC    72  FABURDEN
 73  RECKLING    74  MIRLITON    75  OPAPANAX
 76  BIMBASHI    77  CAATINGA    78  PENSTOCK
 79  SPRINGAL    80  BABIRUSA

HexCheat:

 Edit the file LM3D.EXE with a hexeditor.

 Unlimited time:

 search for              FE 0E 4E 20 79 11
 and change it to        90 90 90 90 79 11
 search for              C7 06 4E 20 00 00
 and change it to        C7 06 4E 20 01 00

 Unlimited tools:

 search for              FE 4F 01 60 B0 11
 and change it to        90 90 90 60 B0 11
 search for              FE 4F 01 64 C6 45
 and change it to        FE 4F 01 64 C6 45