Figured out the local and sram high score saving routines

Code; save high score loop
$01/BE9D 20 E4 BE JSR $BEE4 [$00:BEE4] ;
$01/BEA0 A5 36 LDA $36 [$00:0036] ;
$01/BEA2 05 35 ORA $35 [$00:0035] ;
$01/BEA4 29 F0 AND #$F0 ;
$01/BEA6 F0 3B BEQ $3B [$BEE3] ;
$01/BEA8 22 B7 B2 01 JSL $01B2B7[$01:B2B7] ;
$01/BEAC A2 1F LDX #$1F ;
$01/BEAE AD 85 03 LDA $0385 [$00:0385] ;\
$01/BEB1 10 05 BPL $05 [$BEB8] ; |
$01/BEB3 20 38 BF JSR $BF38 [$00:BF38] ; | if bonus, go to bonus game
$01/BEB6 A2 29 LDX #$29 ; |
$01/BEB8 8E 18 01 STX $0118 [$00:0118] ;/
$01/BEBB A9 F1 LDA #$F1 ;
$01/BEBD 85 4D STA $4D [$00:004D] ;
$01/BEBF EE 20 02 INC $0220 [$00:0220] ;
$01/BEC2 AE 1A 02 LDX $021A [$00:021A] ; load level ID
$01/BEC5 AD 0C 03 LDA $030C [$00:030C] ; load current or high score (whichever is higher)
$01/BEC8 DD B8 02 CMP $02B8,x[$00:02B8] ;\ compare to high score
$01/BECB F0 13 BEQ $13 [$BEE0] ; | branch if you didn't get a high score
$01/BECD 90 11 BCC $11 [$BEE0] ;/
$01/BECF 48 PHA ; push high score
$01/BED0 BD 22 02 LDA $0222,x[$00:0222] ;\
$01/BED3 29 7F AND #$7F ; | branch if you have beat the level before
$01/BED5 F0 08 BEQ $08 [$BEDF] ;/
$01/BED7 BD B8 02 LDA $02B8,x[$00:02B8] ;\
$01/BEDA 09 80 ORA #$80 ; | store old score for the overworld score change (when you get a new high score)
$01/BEDC 8D 20 02 STA $0220 [$00:0220] ;/
$01/BEDF 68 PLA ; pull high score
$01/BEE0 9D B8 02 STA $02B8,x[$00:02B8] ; store new high score
$01/BEE3 60 RTS ; return

Code; high score sram save loop
$10/82B3 A0 00 LDY #$00 ;
$10/82B5 B9 22 02 LDA $0222,y[$10:0222] ;\
$10/82B8 29 01 AND #$01 ; | branch if you've beaten the level
$10/82BA F0 07 BEQ $07 [$82C3] ;/
$10/82BC B9 B8 02 LDA $02B8,y[$10:02B8] ;\
$10/82BF 09 80 ORA #$80 ; | sets the high bit of the high score address to indicate the level has been beaten
$10/82C1 87 00 STA [$00] [$50:0342] ;/ store high score for the level in RAM
$10/82C3 C2 20 REP #$20 ;
$10/82C5 E6 00 INC $00 [$00:0000] ;
$10/82C7 E2 20 SEP #$20 ;
$10/82C9 C8 INY ;
$10/82CA C0 48 CPY #$48 ;
$10/82CC 90 E7 BCC $E7 [$82B5] ;

relevant addresses:

$7E021A level ID

$7E0220 old score for the overworld score change (when you get a new high score)

$7E0222,x log of your history in the level, indexed by level ID

format: X------Y (X = unlocked but not beaten; Y = beaten level)

if none of the bits are set, you haven't unlocked the level yet

$7E02B8,x table of high scores, indexed by level ID

$7E030C current or high score (whichever is higher)

Additionally, I found the bonus item sram save routine:

Code; bonus item sram save loop
$10/82CE A0 00 LDY #$00 ;\
$10/82D0 B9 57 03 LDA $0357,y[$10:0357] ; |
$10/82D3 87 00 STA [$00] [$50:0342] ; |
$10/82D5 C2 20 REP #$20 ; |
$10/82D7 E6 00 INC $00 [$00:0000] ; | save all of your bonus items to sram
$10/82D9 E2 20 SEP #$20 ; |
$10/82DB C8 INY ; |
$10/82DC C0 1B CPY #$1B ; |
$10/82DE 90 F0 BCC $F0 [$82D0] ;/
$10/82E0 C2 20 REP #$20 ;
$10/82E2 AD 82 60 LDA $6082 [$10:6082] ;
$10/82E5 87 00 STA [$00] [$50:0342] ;
$10/82E7 E6 00 INC $00 [$00:0000] ;
$10/82E9 AD 72 03 LDA $0372 [$10:0372] ;
$10/82EC 87 00 STA [$00] [$50:0342] ;
$10/82EE E2 20 SEP #$20 ;
$10/82F0 C2 20 REP #$20 ;

Incidentally, when the game saves your high score to sram, it makes a duplicate table and gets the checksum of it before and after a new high score is added. The process is done thusly:

Code$10/82F2 DA PHX ;\
$10/82F3 DA PHX ; |
$10/82F4 BD 12 80 LDA $8012,x[$10:8012] ; |
$10/82F7 8D 14 30 STA $3014 [$10:3014] ; | get high score checksum before a new high score is added
$10/82FA A2 08 LDX #$08 ; |
$10/82FC A9 83 DE LDA #$DE83 ; |
$10/82FF 22 44 DE 7E JSL $7EDE44[$7E:DE44] ;/ GSU init
$10/8303 FA PLX ;
$10/8304 AD 00 30 LDA $3000 [$10:3000] ;\
$10/8307 9F 70 7E 70 STA $707E70,x[$70:7E70] ;/ store high score checksum
$10/830B BD 12 80 LDA $8012,x[$10:8012] ;\
$10/830E 8D 02 30 STA $3002 [$10:3002] ; |
$10/8311 BD 3A 80 LDA $803A,x[$10:803A] ; |
$10/8314 8D 14 30 STA $3014 [$10:3014] ; | store high scores and get new checksum
$10/8317 A2 08 LDX #$08 ; |
$10/8319 A9 73 DE LDA #$DE73 ; |
$10/831C 22 44 DE 7E JSL $7EDE44[$7E:DE44] ;/ GSU init
$10/8320 FA PLX ;
$10/8321 AD 00 30 LDA $3000 [$10:3000] ;\
$10/8324 9F 76 7E 70 STA $707E76,x[$70:7E76] ;/ store new high score checksum
$10/8328 E2 20 SEP #$20 ;
$10/832A AB PLB ;
$10/832B 6B RTL ;

I've documented the GSU routine as well:

Code; r1 = source table (dw $7C00, $7C68, $7CD0)
; r10 = desination table (dw $7D38, $7DA0, $7E08)
; indexed by save file
0008:DE73 2A 12 move r2,r10 ; move desination into r2
0008:DE75 02 cache ;\ table copy loop
0008:DE76 FC 34 00 iwt r12,#0034 ; | load number of high scores to save (number of levels total)
0008:DE79 FD 7C DE iwt r13,#DE7C ; | set loop address
0008:DE7C 41 ldw (r1) ; |\ copy high score from source table to desination table
0008:DE7D 32 stw (r2) ; |/
0008:DE7E D1 inc r1 ; |\
0008:DE7F D1 inc r1 ; | | loop until every high score is saved
0008:DE80 D2 inc r2 ; | |
0008:DE81 3C loop ; |/
0008:DE82 D2 inc r2 ;/
; r10 = destination
0008:DE83 02 cache ;\ checksum loop
0008:DE84 FC 34 00 iwt r12,#0034 ; | load number of high scores
0008:DE87 FD 8C DE iwt r13,#DE8C ; | set loop address
0008:DE8A A1 00 ibt r1,#00 ; |
0008:DE8C 4A ldw (r10) ; | load destination table
0008:DE8D 11 51 add r1 ; | add score to r1
0008:DE8F DA inc r10 ; |\
0008:DE90 3C loop ; | | loop through every index ($34 times)
0008:DE91 DA inc r10 ;/ /
0008:DE92 F0 77 77 iwt r0,#7777 ;\ compute checksum
0008:DE95 61 sub r1 ;/ r0 = final checksum
0008:DE96 00 stop ;\ halt gsu processing
0008:DE97 01 nop ;/

The checksum of the duplicate table before the copy is stored to $707E70,x; the checksum of the table after the copy is stored to $707E76,x. Both are indexed with the save file.

Warning: Opinions expressed by Lexie or others in this post do not necessarily reflect the views, opinions, or position of Lexie himself on the matter(s) being discussed therein.

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