Issue with Wood Roof Frame w/ Tie Beam Model - Large Displacements?

I'm new to STAAD and attempting to model a simple roof frame for a 1-story home with a tie beam. For some reason I am getting exceptionally large displacements (52") even though my loading is pretty light (dead, snow, wind) total of ~100plf max.

Of note: The furthest out supports are the walls w/ a 1' overhang. The inner two supports are "girders" going in the Z-direction which the rafters will be notched and attached too.

Here is my command file:

STAAD SPACE
START JOB INFORMATION
JOB NAME PSU Project
JOB CLIENT PSU
JOB REV 0
ENGINEER NAME Hunter Brooks
ENGINEER DATE 8/21/2023
END JOB INFORMATION
INPUT WIDTH 79
UNIT INCHES KIP
JOINT COORDINATES
1 408 0 0; 2 180 38 0; 3 0 -37 0; 4 396 2 0; 5 12 -32 0; 6 318 15 0;
7 124.8 15 0; 8 93.25 1.854 0; 9 340.75 11.208 0;
MEMBER INCIDENCES
1 1 4; 2 2 7; 3 4 9; 4 5 3; 5 6 2; 6 7 8; 7 7 6; 8 8 5; 9 9 6;
DEFINE PMEMBER
2 6 8 4 PMEMBER 1
1 3 9 5 PMEMBER 2
SUPPORTS
4 5 8 9 PINNED
UNIT INCHES POUND
DEFINE MATERIAL START
ISOTROPIC TIMBER
E 1.5e+06
POISSON 0.15
DENSITY 0.0144676
ALPHA 3e-06
DAMP 0.06
G 652174
TYPE TIMBER
ISOTROPIC DFL
E 1600
POISSON 0.15
DENSITY 0.01806
ALPHA 3e-06
DAMP 0.06
G 652174
TYPE TIMBER
END DEFINE MATERIAL
MEMBER PROPERTY
1 TO 6 8 9 PRIS YD 9.25 ZD 1.5
7 PRIS YD 3.5 ZD 1.5
CONSTANTS
MATERIAL DFL ALL
MEMBER RELEASE
7 END MX MY MZ
7 START MX MY MZ
DEFINE REFERENCE LOADS
LOAD R1 LOADTYPE Dead TITLE DEAD
LOAD R2 LOADTYPE Snow TITLE SNOW
LOAD R3 LOADTYPE Wind TITLE WIND
END DEFINE REFERENCE LOADS
LOAD 1 LOADTYPE Dead TITLE DEAD
PMEMBER LOAD
1 UNI GY -2
2 UNI GY -1.167
LOAD 2 LOADTYPE Snow TITLE SNOW
PMEMBER LOAD
1 2 UNI GY -3.333
LOAD 3 LOADTYPE Wind TITLE WIND
PMEMBER LOAD
1 2 UNI GY -3.133
LOAD COMB 4 D+S
1 1.0 2 1.0
LOAD COMB 5 D+.75S+.45W
1 1.0 2 1.0 3 1.0
PERFORM ANALYSIS
DEFINE ENVELOPE
4 ENVELOPE 1
5 ENVELOPE 2
END DEFINE ENVELOPE
FINISH

Any help would be appreciated! Thanks!