added check

iz_helpers/ui.py

@@ -256,7 +256,7 @@ Our best experience and trade-off is the R-ERSGAn4x upscaler.
                     "infinite-zoom", shared.opts.outdir_img2img_samples
                 )
         generate_btn.click(
-            fn=wrap_gradio_gpu_call(create_zoom, extra_outputs=[None, "", ""]),
+            fn=wrap_gradio_gpu_call(check_create_zoom, extra_outputs=[None, "", ""]),
             inputs=[
                 main_common_prompt_pre,
                 main_prompts,
@@ -291,3 +291,67 @@ Our best experience and trade-off is the R-ERSGAn4x upscaler.
         interrupt.click(fn=lambda: shared.state.interrupt(), inputs=[], outputs=[])
     infinite_zoom_interface.queue()
     return [(infinite_zoom_interface, "Infinite Zoom", "iz_interface")]
+
+
+
+def check_create_zoom(
+                main_common_prompt_pre,
+                main_prompts,
+                main_common_prompt_suf,
+                main_negative_prompt,
+                main_outpaint_steps,
+                main_guidance_scale,
+                sampling_step,
+                init_image,
+                exit_image,
+                video_frame_rate,
+                video_zoom_mode,
+                video_start_frame_dupe_amount,
+                video_last_frame_dupe_amount,
+                inpainting_denoising_strength,
+                inpainting_mask_blur,
+                inpainting_fill_mode,
+                inpainting_full_res,
+                inpainting_padding,
+                video_zoom_speed,
+                seed,
+                main_width,
+                main_height,
+                batchcount_slider,
+                main_sampler,
+                upscale_do,
+                upscaler_name,
+                upscale_by, 
+):
+    keys = main_prompts.keys()
+    if 0 not in keys:
+        raise gr.Error("Ensure your prompt table has a step 9 (zero) prompt")
+    
+    return create_zoom(                main_common_prompt_pre,
+                main_prompts,
+                main_common_prompt_suf,
+                main_negative_prompt,
+                main_outpaint_steps,
+                main_guidance_scale,
+                sampling_step,
+                init_image,
+                exit_image,
+                video_frame_rate,
+                video_zoom_mode,
+                video_start_frame_dupe_amount,
+                video_last_frame_dupe_amount,
+                inpainting_denoising_strength,
+                inpainting_mask_blur,
+                inpainting_fill_mode,
+                inpainting_full_res,
+                inpainting_padding,
+                video_zoom_speed,
+                seed,
+                main_width,
+                main_height,
+                batchcount_slider,
+                main_sampler,
+                upscale_do,
+                upscaler_name,
+                upscale_by,
+    )